2,224 research outputs found

    Ultraviolet and Infrared Spectra of Some p-Nitrobenzyl Phenyl Ethers

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    The UV-spectra of substituted p-nitrobenzyl phenyl ethers in ethanol and carbon tetrachloride were recorded. The effect of substitution on band position and intensity is correlated with the electronic nature of the group. The IR-spectra are analysed and the position of certain bands ii;; dis.cussed in terms of molecular structure

    Building the capacity of agricultural extension personnel for effective implementation of agricultural transformation agenda in Nigeria

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    This paper reviews the capacity (number, quality and motivation) of the extension personnel in Nigeria; and describes farmers’ perception of the quality of extension service delivery using evidences from literature, reports of organizations as well as experiences from field research. Findings reveal a tremendous shortage in the number and quality of extension personnel across the country as major reason for the poor performance of the ADPs thereby leaving no hope for the “beautiful†transformation agenda. This paper strongly recommends immediate recruitment of new hands as well as full implementation of a well-designed capacity building programme so as to ensure a sustainable extension service delivery system where extension personnel can operate in the expected commercial (agriculture-driven) economy

    Building the capacity of agricultural extension personnel for effective implementation of agricultural transformation agenda in Nigeria

    Get PDF
    This paper reviews the capacity (number, quality and motivation) of the extension personnel in Nigeria; and describes farmers’ perception of the quality of extension service delivery using evidences from literature, reports of organizations as well as experiences from field research. Findings reveal a tremendous shortage in the number and quality of extension personnel across the country as major reason for the poor performance of the ADPs thereby leaving no hope for the “beautiful†transformation agenda. This paper strongly recommends immediate recruitment of new hands as well as full implementation of a well-designed capacity building programme so as to ensure a sustainable extension service delivery system where extension personnel can operate in the expected commercial (agriculture-driven) economy

    A New Probe of the Molecular Gas in Galaxies: Application to M101

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    Recent studies of nearby spiral galaxies suggest that photodissociation regions (PDRs) are capable of producing much of the observed HI in galaxy disks. In that case, measurements of the HI column density and the far-ultraviolet (FUV) photon flux provide a new probe of the volume density of the local underlying H_2. We develop the method and apply it to the giant Scd spiral M101 (NGC 5457). We find that, after correction for the best-estimate gradient of metallicity in the ISM of M101 and for the extinction of the ultraviolet emission, molecular gas with a narrow range of density from 30-1000 cm^-3 is found near star- forming regions at all radii in the disk of M101 out to a distance of 12' (approximately 26 kpc), close to the photometric limit of R_25 = 13.5'. In this picture, the ISM is virtually all molecular in the inner parts of M101. The strong decrease of the HI column density in the inner disk of the galaxy at R_G < 10 kpc is a consequence of a strong increase in the dust-to-gas ratio there, resulting in an increase of the H_2 formation rate on grains and a corresponding disappearance of hydrogen in its atomic form.Comment: accepted for publication in The Astrophysical Journal (1 August 2000); 29 pages including 20 figures (7 gif); AAS LaTex; contact authors for full resolution versions of gif figure

    X-Ray Spectral Study of AGN Sources Content in Some Deep Extragalactic XMM-Newton Fields

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    We undertake a spectral study of a sample of bright X-ray sources taken from six XMM-Newton fields at high galactic latitudes, where AGN are the most populous class. These six fields were chosen such that the observation had an exposure time more than 60 ksec, had data from the EPIC-pn detector in the full-Frame mode and lying at high galactic latitude b>25o|b| > 25^o . The analysis started by fitting the spectra of all sources with an absorbed power-law model, and then we fitted all the spectra with an absorbed power-law with a low energy black-body component model.The sources for which we added a black body gave an F-test probability of 0.01 or less (i.e. at 99% confidence level), were recognized as sources that display soft excess. We perform a comparative analysis of soft excess spectral parameters with respect to the underlying power-law one for sources that satisfy this criterion. Those sources, that do not show evidence for a soft excess, based on the F-test probability at a 99% confidence level, were also fitted with the absorbed power-law with a low energy black-body component model with the black-body temperature fixed at 0.1 and 0.2 keV. We establish upper limits on the soft excess flux for those sources at these two temperatures. Finally we have made use of Aladdin interactive sky atlas and matching with NASA/IPAC Extragalactic Database (NED) to identify the X-ray sources in our sample. For those sources which are identified in the NED catalogue, we make a comparative study of the soft excess phenomenon for different types of systems

    Synthesis, Characterization and Antimicrobial Activities of Some Nicotinamide – metal Complexes

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    Some transition metal complexes of nicotinamide have been prepared and characterized using melting point, conductivity measurement, infrared, electronic, HNMR and atomic absorption spectroscopic methods. . The antibacterial and antifungal studies of the metal complexes and the ligand have been evaluated against Escherichia coli, Staphylococcus and Bacillus subtilis , Aspergillus flavus, Aspergillus niger and penicillum species. It was found that nicotinamide formed stable metal complexes with these metal ions. The analysis of the spectroscopic data shows that nicotinamide act as monodentate, coordinating through the nitrogen atom of the pyridine ring. All the complexes exhibit 4- coordinate geometry. The results of the antimicrobial studies showed that the metal complexes have higher inhibitory activity than the original nicotinamide against the tested bacteria and fungi species.Keywords: Synthesis, Metal complexes, Nicotinamide, Antibacterial, Antifunga

    Morphological assessment of Niger Kuri cattle using multivariate methods

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    A total of 406 adult cows and 34 bulls belonging to the Niger Kuri cattle population were assessed for 16 body measurements and 11 qualitative traits to contribute to the characterization of this unique cattle breed. Body measurements included facial, horn, ear and rump lengths; facial, cranial, shoulder, pelvic and ischium widths; height at withers and at hips; muzzle circumference; heart girth; body and tail lengths; and thorax depth. Qualitative traits included cephalic profile, ear shape, muzzle pigmentation, eyelid pigmentation, hoof pigmentation, horn colour, dewlap size, backline profile, horn shape, spotting pattern, and coat colour pattern. Data were analysed jointly with 377 individuals from four other West African taurine cattle breeds (N’Dama, Lagunaire, Lobi and Somba) using multivariate statistical methods, including canonical and correspondence analyses. Among the breeds analysed, Kuri cattle had the highest mean values for all body measurements: height at withers and body length had mean values of 124.0 ± 0.4 and 146.8 ± 1.0 cm in Kuri cows, respectively, and 126.0 ± 2.2 and 155.7 ± 3.6 cm, respectively, in Kuri bulls. Canonical analysis allowed the construction of contour plots to illustrate the high differentiation between Kuri cattle and the other breeds, regardless of the sex of the individuals. Further, the Mahalanobis distance matrices showed that pairs involving Kuri cattle had the higher differentiation of these populations. Correspondence analysis carried out on these 11 qualitative traits allowed the researchers to ascertain a clear differentiation between the Kuri and the other taurine cattle breeds. The N’Dama, Lagunaire, Lobi, and Somba breeds did not show clear differentiation at qualitative-type trait level with 75% confidence regions computed for these four breeds being highly intermingled. In the current data, Kuri cattle had the highest frequency in qualitative features, such as concave cephalic profile, dropped ears, non-pigmented muzzle and grey-coloured horns, which are absent in West African taurine and zebu cattle breeds, according to the literature. The current evidence would suggest that unique Kuri cattle type features may result from breeding decisions rather than from zebu admixture. This work confirms that at type trait level Kuri cattle is a unique population within the West African taurine cattle group. The implementation of genetic analyses aiming at ascertaining the degree of uniqueness of the breed is advised.Keywords: Body measurements, Bos taurus, multivariate analyses, qualitative traits, West African cattl

    Effects of sand and gating architecture on the performance of foot valve lever casting components used in pump industries

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    Funding Information: The authors thank Kalasalingam Academy of Research and Education, Krishnankoil for providing the facilities for various tests and characterizations. The King Saud University authors extend their appreciation to the Deanship of Scientific Research at King Saud University for funding the work through the research group project no. RG-148. This Research was funded by King Mongkut's University of Technology North Bangkok has received funding support from the National Science, Research and Innovation Fund (NSRF) (Grant No. KMUTNB-MHESI-64-16.1). Publisher Copyright: © 2021 The Author(s)This work addresses manufacture, testing and simulation of foot valve lever (FVL) for monoblock pump industry, using a cost-effective casting design process. The impact of different types of sands, such as air-set, dry and sodium silicate as well as gating designs, namely H-, U- and O-type, were studied with respect to surface roughness and porosity. The mold pattern was produced using additive manufacturing (AM) technology. Both experimental and numerical investigations were performed on the temperature distribution of molten metal at random locations for the different gating configurations or designs, considering mold filling and solidification. It was evident from the experimental investigation that contribution of air-set sand and O-type gating architecture showed limited consistency effects. Importantly, gating architecture was the most influential parameter to determine all specified quality outcomes, independent of sand mold. An order of O < H < U-type was obtained from the gating designs for minimal surface roughness and percentage of porosity. Furthermore, the microstructure analysis depicted only an irregular defect with minimum quantity at both surface and cross-section of O-type at two different locations. Optimum pouring temperatures of 740, 750 and 790 °C were obtained for mold filling of all 24 components of H-, O- and U-type of gating designs, respectively. The varying solidification temperature was observed from real time thermocouple reading, which was in close agreement with the numerical simulation. Evidently, O-type of gating design exhibited best performance for large-scale development of the FVL in terms of surface roughness, porosity and cooling effects.Peer reviewe
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