scholarly journals Surface Radio Refractivity of Akure and Ondo town, Southwest Nigeria

2021 ◽  
Vol 4 (1) ◽  
pp. 212-219
Author(s):  
IP Onujagbe ◽  
F Ahmed-Ade ◽  
M Mopah ◽  
AJ David

The surface radio refractivity, refractivity gradient at 1km above ground surface and the effective earth radius factor, K over Akure and Ondo town of South west Nigeria has been investigated using Ten (10) years daily data of the meteorological parameters of Pressure, air temperature and humidity. The result showed that the mean monthly value of the surface refractivity at the Ondo station is generally slightly higher than that of Akure. The monthly mean value of refractivity at the two stations was found to be strongly correlated with a value of 0.915. The most negative refractive gradient value observed at Ondo and Akure are of -46.48N-units/km and -45.64N-units/km respectively and the least effective earth radius factor, k value of 1.421 and 1.410 were observed at the station respectively. These results showed that the Ondo and Akure station were generally super-refractive. The Ondo station was however found to be slightly more super-refractive than the Akure station.

2021 ◽  
Vol 900 ◽  
pp. 183-187
Author(s):  
Odunlami Olayemi Abosede ◽  
Akeredolu Funso Alaba

The emissions of carbon monoxide, carbon dioxide, and hydrocarbon from four stroke-powered motorcars and two stroke-powered motorcycles and tricycles in Southwest Nigeria were examined using an automotive 4-gas analyer. Results show that tricycles produced more hydrocarbon and carbon monoxide emissions than motorcycles, while motorcycles emitted more of these pollutants than the gasoline fueled motor cars. (The gasoline fueled motorcars produced lowest hydrocarbon and carbon monoxide while the tricycles produced the highest hydrocarbon and carbon monoxide emissions). On the contrary, motor cars had the highest mean value of carbon dioxide followed by the motorcycles, while tricycles had the least. This could be attributed to the presence of the catalytic converters in some of the motor cars oxidizing carbon monoxide to carbon dioxide. The mean values of hydrocarbon, carbon monoxide and carbon dioxide emissions from motorcars are 630ppm, 10200ppm and 59900ppm. This is much higher than the NESREA (National Environmental standards and Regulations Enforcement Agency) standards as well as Euro II and Euro III (European standards) for vehicular emission. The mean values for hydrocarbon, carbon monoxide and carbon dioxide emissions from motorcycles and tricycles are (2150ppm, 21530ppm and 31200ppm) and (2820ppm, 24880ppm and 38710ppm) respectively. These results do not comply with Nigeria and European emission standards for hydrocarbon, and carbon monoxide. Tricycles and motorcycles account for higher concentrations of hydrocarbon and carbon monoxide pollutants from mobile sources, while they emit carbon dioxide minimally.


1960 ◽  
Vol 11 (1) ◽  
pp. 27 ◽  
Author(s):  
SA Waring ◽  
LJH Teakle

The level of mineral nitrogen in the soil under fallow and crop was measured for the years 1951 to 1953. Relationships of mineral nitrogen at planting to yield and nitrogen content of wheat grain and straw were examined. Values for nitrate nitrogen at the end of the fallow period ranged most commonly from 10 to 20 µg/g in the surface 2 ft and from 0 to 10 µg/g at 2-4 ft. Approximately one-third of the sites showed an increase from the third to the fourth foot. One site showed extremely high values throughout the profile, particularly at 3-4 ft where a value of 127 µg/g was recorded. Values for ammonia nitrogen were most commonly in the range of 0-3 µg/g . Under the growing crop, mineral nitrogen declined for most depths in the period from planting up to September or October, after which there was little further change to harvest. Uptake of mineral nitrogen was normally greatest from the surface 2 ft of soil. Below 3 ft there were two groups of sites. One group showed moderate to high uptake and the second group low uptake. The low uptake in the latter group provides a reason for mineral nitrogen accumulation below 3 ft at some sites. Mineral nitrogen to 4 ft at planting averaged 126 lb/ac, excluding the one site with exceptionally high values. This was double the mean value of 63 lb/ac for nitrogen recovered in grain and straw, for crops planted in May-June. These figures, combined with trends in the soil under crop, suggest that most of the nitrogen used by the crop was derived from that in the soil at planting. Correlations between mineral nitrogen at planting and grain yield were mostly non-significant, suggesting that in general nitrogen was not an important factor limiting yield. Low grain yield and protein percentage were recorded at a number of sites which had been cultivated more than 50 years.


Author(s):  
Musa'adatul Fithriyah

The Qur'an learning is very fundamental in Islamic education, especially in elementary education. The Qur'an is one of the subjects that must be taught to children. Early education in the Qur'an is expected to produce young people having a strong mental foundation, education not only makes children as prosperous in the world, but also provides sufficient provisions to both improve their religion and practice their scriptures. To be able to practice the Holy Qur'an correctly, children must be guided and taught how to read the Qur'an properly in accordance with the rules of true recitation. In fact the Qur'an learning at MI AL-Hidayah Mangkujajar Kembangbahu Lamongan initially tended to be monotonous for being dominated by conventional learning methods. As a result,  the Qur'an learning only produced generations that could read the Qur'an with the average ability without any sense of love and closeness to the Qur'an instead of having enthusiasm in learning it well. As time goes by, the Qur'an learning at MI Al-Hidayah has increasingly developed by applying the so-called Wafa method. This method teaches children to be able to read and memorize the Qur'an by maximizing the right brain. This is classified as a new method, but it is quite practical and fun in the learning process. The research was aimed at determining the effect of the Wafa method on the ability of children to read the Qur'an at MI Al-Hidayah Mangkujajar Kembangbahu Lamongan. The research method is quantitative with the experimental type of one group pretest-post test, data analysis techniques use the mean pretest and posttest, in addition, to testing the hypothesis it uses the Paired Sample T-Test with the SPSS 16. The results showed the influence of the Wafa method on the children ability to read the Qur'an at MI Al-Hidayah Mangkujajar Kembangbahu Lamongan. It was proven from the results of the analysis through the mean pretest formula, it was obtained a value of 82.92 and increased in the acquisition of the mean value of posttest amounted to 85.75. In addition, in the Paired Sample T-Test based on significance values with SPSS 16, it is known that the Sig. (2-tailed) value is 0,000 <0,05, because sig. (2-tailed) of 0,000 is smaller than 0.05, then the hypothesis is accepted and it could be concluded that there is an influence of the WAFA Method on the ability to read the Qur'an at MI Al-Hidayah Mangkujajar Kembangbahu Lamongan.


2019 ◽  
Author(s):  
Aïssé Florence Judith Trébissou ◽  
Chiayé Claire Antoinette Yapo-Crezoit ◽  
Pascal Sibailly ◽  
Mamadou Sanogo ◽  
Amos Ankotché ◽  
...  

AbstractBackgroundDiabetes autoantibodies are indispensable markers of diabetes classification.Objectiveto research autoantibodies anti-GAD and anti-IA2 in type 1A diabetics (T1D) aged 5 to 21 years, and to follow the progression of these autoantibodies in T1D patients, in Côte d’Ivoire.MethodsThe study population composed of 28 T1D patients, aged 5 to 21 years. T1D were followed up in two diabetes care centers in Abidjan district, Endocrinology departments of U.H.C of Yopougon and Treichville. Anti-GAD and anti-IA2 autoantibodies were researched by ELISA.Resultsanti-GAD and anti-IA2 were present in T1D and their siblings. After 2 years of diabetes, the titer of the anti-GAD autoantibodies increased to the mean value of 677.10 ± 353.20 IU / ml. Then, a fall of the anti-GAD autoantibodies until the cancellation was observed from the 8th to the 9th with values of 117 IU / ml to 10.14 IU / ml. Anti-IA2 autoantibodies fall at 9th year of diabetes with a value of 55.10 IU / ml.Conclusionanti-GAD and anti-IA2 autoantibodies persist after 9 years of diabetes, causing total destruction over time of the pancreatic β-cell mass in patients from Côte d’Ivoire, leading them to the death.


1968 ◽  
Vol 46 (20) ◽  
pp. 2325-2329 ◽  
Author(s):  
Janet S. Merritt ◽  
R. E. Green

The 2200 m/s neutron activation cross section of 59Co has been determined with respect to 197Au by irradiating gold and cobalt foils in a thermal neutron flux. The result for the production of 5.261-year 60Co both directly and through 60Com is[Formula: see text]based on a value of σ0 = 98.7 b for, 197Au. Allowing for the 60Com that decays directly to levels in 60Ni yields a value for the 2200 m/s capture cross section of[Formula: see text]The standard deviation of the mean value of seven determinations was ± 0.06 %. The quoted error of ± 0.27 b has been derived from estimates of systematic errors that are discussed.


1979 ◽  
Vol 57 (5) ◽  
pp. 524-528 ◽  
Author(s):  
James L. Barnhart ◽  
Burton Combes

The apparent volume of the biliary tree (ABV) in the dog was determined by measuring the mean biliary transit time of injected [14C]taurocholate ([14C]TC). After bolus injection of [14C]TC, entry of bile salt into the lumen of the biliary tree is signaled by an increase in bile flow. The volume of bile collected at the common duct from onset of choleresis until maximal concentration of 14C radioactivity is reached in bile minus the calculated quantity of bile that contains radioactivity and the cannula volume yields a value for the volume of the biliary tree present just prior to injection of [14C]TC. The mean value for ABV in 19 dogs was 2.49 ± 0.65 μL/g liver (mean ± SD).


1959 ◽  
Vol 50 (1) ◽  
pp. 135-149 ◽  
Author(s):  
F. L. Vanderplank

SummaryIn the second of this series of papers on the losses caused by the Coreid, Pseudotheraptus wayi Brown, to coconuts in Zanzibar, descriptions are given in summary form of a number of Government-owned plantations of coconuts on the island, together with the yields recorded over the 12 years, 1944–55. The variation from year to year in any group of plantations is not large, and over all those considered does not exceed 25·8 per cent, of the 12-year mean.In the plantations on poorer soils, predominantly occupied by the ants Anoplolepis longipes (Jerd.) or A. custodiens (F. Sm.), the vidaka damage rate (V.D.R.) during 1955 varied from 60–80. The plantations on better soils are occupied predominantly by a complex of Oecophylla longinoda (Latr.) and Pheidole punctulata Mayr and the V.D.R. determined on a part of these in 1955–56 varied from approximately 41 to 55, with a mean of 47·1. The mean value of the V.D.R. calculated from 200 localities taken at random in Zanzibar during June–August 1955 was 60·6. Taking a value of 50 as a conservative estimate of the V.D.R. for the whole island, and inserting this in the regression equation Y = a + bX relating yield (Y) with V.D.R. (X), derived in the first of this series of papers, together with the average values of the constants a and b obtained therein, it is shown that about two-thirds of the potential crop of coconuts is lost as a result of damage by P. wayi.Comparison of the yields from palms occupied by Oecophylla in two of the plantations on better soil with those of the whole of those plantations suggests that about one-half of the potential crop is being lost.The annual value of the total exports of unconverted nuts and coconut products (copra and coconut oil) varied from £636,254 to £1,008,194 during 1949–56, and the annual value of the total production of nuts, calculated from the estimated total acreage (104,000), the number of palms per acre (50), the 12-year average yield per palm on Government-owned plantations (22·5 nuts per annum) and the market price in 1948–56 (Shgs. (E.A.) 90–150 per thousand nuts), is £526,500 to £877,500. Taking into consideration the lower and upper estimates of the amount of crop lost and of the value of what remains, the minimum and maximum estimates of the financial loss caused by P. wayi in Zanzibar are of the order of £500,000 and £2 million, respectively.


Nafta-Gaz ◽  
2021 ◽  
Vol 77 (1) ◽  
pp. 10-19
Author(s):  
Marian A. Szurgot ◽  

The thermal conductivity (K) of Jezersko H4 meteorite was predicted by various models of rocks, using literature data on the chemical composition, porosity (P), and by relationships between thermal conductivity and porosity, and between thermal conductivity and thermal diffusivity (D). The results confirm that the porosity of the chondrite and air pressure significantly affect thermal conductivity. The thermal conductivity of the chondrite skeleton/matrix predicted by the modal composition of the meteorite and by the geometric mean model is equal to 4.35 W m−1 K−1, and by arithmetic and harmonic mean models: 4.9 W m−1 K−1at 300 K. Bulk thermal conductivity of the meteorite predicted by the geometric mean model is equal to 2.6 W m-1 K-1 for air pressure of 1 atm, and 1.0 W m−1 K−1in vacuum at 300 K. The Hashin–Shtrikman model predicts the values: 2.4 and 1.9 W m−1 K−1, the Clausius–Mossotti model: 2.2 and 1.9 W m-1 K-1, and the mean of two-layer models: 2.1 and 2.0 W m−1 K−1 at 300 K, for air pressure of 1 atm, and in vacuum, respectively. The relationships between thermal conductivity and porosity based on experimental data for ordinary chondrites indicate a mean K value for bulk thermal conductivity of the Jezersko meteorite in vacuum: 1.18 W m−1 K−1, and between thermal conductivity and thermal diffusivity the mean value: 1.12 W m−1 K−1at 200–300 K. The mean value for all predictions for bulk thermal conductivity of the meteorite for air at 1 atm is equal to 2.45 ± 0.30 W m−1 K−1 (range: 2.0–2.9 W m−1 K−1) at 300 K, and in vacuum: 1.40 ± 0.40 W m−1 K−1 (range: 0.95–2.0 W m−1 K−1) at 200–300 K. Predicted values of bulk thermal conductivity of the Jezersko meteorite, for air and in vacuum, are in the range of values recently reported by Soini et al. (2020) for the H4 group of chondrites: 2.8 ± 0.6 W m−1 K−1, mean K for air at 1 atm, and 1.9 ± 1.0 W m−1 K−1 mean K value in vacuum at 200–300 K.


Author(s):  
A. T. Adediji ◽  
S. O. Adebusola ◽  
J. S. Ojo

In this study, results of the variation of maximum and minimum radio horizon distance derived from the computation of surface refractivity through measurement of temperature, relative humidity and pressureacrosssevenlocations((Akure (7.15°N, 5.12°E), Lagos (6.30°N, 3.20°E), Abuja (7.10°N, 9.25°E), Jos (9.50°N, 8.50°E), Makurdi (7.30°N,8.53°E), Port-Harcourt(4.20°N,7.00°E), and Nsukka (6.90°N,7.67°E)) in Nigeria are presented. Two years (Jan., 2011–Dec., 2012) archived data as provided by Tropospheric Data Acquisition Network (TRODAN) of the Centre for Atmospheric Research Anyigba, Kogi State were utilized for the study. Results showed that the values of surface refractivity (Ns) were low during the dry season months and high during the wet season months and also there was high value of NS at the coastal areas compared with the inland areas. It was also deduced that the mean value of NS for Abuja, Akure, Jos, Lagos, Markurdi, Nsukka and Port-Harcourt is 355, 362, 303, 391, 375, 361 and 399 N-units respectively. Results showed that the Radio Horizon Distance (RDH) values were generally low during the wet season months and high during the dry season months. The variability of radio horizon distance of transmitting antennas is higher in the Northern part of Nigeria than the southern part.


2012 ◽  
Vol 429 ◽  
pp. 9-13
Author(s):  
Xin Li Tian ◽  
Jian Quan Wang ◽  
Fang Guo ◽  
Ke Ling Lin

Surface roughness is one of the key factors to evaluate the grinding quality for engineering ceramics. This study introduces a new method based on grayscale information of surface images, to assess and predict the roughness of ground ceramics rapidly and effectively. The investigation sets the functional parameters of digital acquisition device as Brightness 140, Contrast 42, Saturation 24 and Acutance 9. Afterwards, it selects the mean value and the mean square deviation to describe surface roughness, and some image processing techniques are adopted to reduce noises and enhance the images. Lastly, it gives the relation curves on Ra,Rz,Ry versus grayscale information, and concludes a direct proportion law between the grayscale information and ground surface roughness.


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