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- " Road tankers are the most used means of transporting petroleum product to end users due to its cost effectiveness and energy-efficiency. The cylindrical tank has been well designed for by ASME VIII divisions 1 and 2 using analytical equations. Petrol tankers are not circular but elliptical probably for stability during transportation. This paper has used the finite element method to investigate in-plane displacements and Von-Mises stresses in both circular and elliptical cylindrical tanks under full loading. An elliptical OANDO? tanker of 66.78 m3volume and shell thickness of0.2 mmand an equivalent volume circular cylindrical tank was used for the simulation. MATLAB? was used to generate geometrical mesh model of the petroleum tankers, extract element coordinates and conduct the finite element analysis. Plane strain condition was used in analyzing a section of the petroleum tanker. It was observed that an equivalent volume circular cylindrical tank was under a higher internal pressure (16,858 N/m2) compared to the elliptical cylinder (14,480 N/m2). Von-Mises stress and in-plane displacements showed direct linear relationships with internal fluid pressure. Von-Mises stress in the elliptical tank was found to be lower (5.7 × 106 N/m2) than for the circular tank (8 × 106 N/m2). In plane displacements was zero in the longitudinal direction for both tanks and of the order of 10-4 mm in the y-direction for both tanks with the circular larger by about 2.5 × 10-3 cm. So in addition to tank stability on the lorry, the Von-Mises stresses were lower as well for the elliptical tank. It was also observed that Von-Mises stresses were far below the yield stress of the steel plate. However, the effect of weldment area on lowering of yield stress was not studied. Stress values were validated using analytical method and found to be insignificantly different (P > 0.05). " 1 results 1
- "This study investigated the characterisation of the dynamic responses of 3-dimensional Lorenz and Rӧsler models by Lyapunov's exponents using popular but laborious to implement Grahm Schmidt orthogonal rules over wider range of models driven parameters. The study also verifies a new proposed model for the validation of Lyapunov's spectrum when the requisite matrix depends on positions on the model attractor. Models and the corresponding Lyapunov's spectrums were simulated by appropriately effecting Grahm Schmidt orthogonal rules and using three different detailed constant step Runge-Kutta algorithms. The FORTRAN-90 coded algorithms were validated using literature results reported by Vladimir Golovko (2003). The stability of Lyapunov's exponents estimate variation was studied in the range of estimate reset period of 2≤τ≤16 .The Lorenz model was characterized at δ = 10, ƿ =28, and 1≤β≤2.8. This range covers both square and rectangular geometries. Similarly, Rӧsler model was characterised at a=ᵞ=0.2 and 2≤µ≤6. This range has potential to drive the model both periodically and chaotically depending on the choices of µ .The validation of the largest Lyapunov's exponents (λ)in Rosier model suffered the highest relative absolute percentage error of 14.29 while its absolute error is one of the lowest (0.01). The remaining five Lyapunov's exponents (three from Lorenz and two < from Rӧsier) suffered relative absolute percentage error of ≤ 2.00. Estimated Lyapunov's exponents stabilise for estimate reset period ≤ 10 .The most stable algorithms was found to be Butcher's modified fifth order followed respectively by fourth (RK4) and fifth (RK5) order. Estimation of Lyapunov's exponents' in Rӧsier model was found to be insensitive to algorithms due to its relative low degree of nonlinearity when compared with Lorenz model. It was established that the sum of Lyapunov's spectrum is the same as the average of trace of variation square matrix over large iteration regardless of dependence on position variable or not. This study demonstrated that the utility of Lyapunov's exponents as response characterising tool of dynamic systems driven by different parameters combination justify its laborious estimation by Grahm Schmidt method. " 1 results 1
- 4-Carboxyl-2 1 results 1
- 6-dinitrobenzenediazonium ion (CDNBD) 1 results 1
- A large number of hetero-aromatic and carbonyl molecules are useful in pharmaceutical and dye industries. Studies of their transition dipole moment (∆μ) and transition polarizability (∆α) are important because they determine their solubility and usefulness. Experimental determination of these parameters and other electronic properties such as oscillator strength (f) using Solvatochromic Shift Equations (SSE) has proved to be unreliable. This is due to the large spread in their reported values and the overlapping of the electronic transition bands for a given molecule. This study was designed to modify the SSE in improving its reliability, and to computationally determine the photophysical properties of some hetero-aromatic and carbonyl compounds with a view to studying the extent of overlap of the electronic transition bands. The ultra-violet spectra of 2,3-diphenylcyclopropenone; 9,10-phenanthrenequinone; Furan-3,4-dicarboxylic acid; 3,4-diphenylthiophene; 3,4-dicarboxylic-2,5-diphenylthiophene and benzo[b]thiophene in the wavenumber range (25,000 - 52,631) cm-1, in solvents of different polarities at concentrations range of 10-6 - 10-5 M were measured at 25oC. These compounds were selected for the modified SSE due to the variation in their structures. The magnitudes of f in solution (fs) and in vapour phase (fv) were calculated using the Onsager-Abe reaction field model equations. The frequencies of electronic transitions in various solvents were used to characterise the observed bands. The SSE was modified by incorporating the molecular ground state polarizability (α), the molar refraction of each compound, Einstein coefficient and stark term. Estimation of the Δµ and Δα of these compounds were determined using the modified SSE. The electronic properties: f, number of transitions, the frontier orbitals energy gap (ΔELUMO-HOMO) and associated parameters such as: Ionization Potential (IP) and global hardness (ƞ) of the optimized structures of the molecules were calculated based on Time-Dependent Density Functional Theory using Becke’s three parameter with Lee-Yang-Parr modification and 6-31G* basis set. The spectra of these compounds gave a range of one to five bands designated as S0-S1, S0-S2, S0-S3, S0-S4 and S0-S5 in order of increasing energy. The magnitudes of fs and fv for the observed bands increased with increasing solvent polarities and were within the range 3.2x10-4 - 1.78 and 3.1x10-4 - 1.33 for hetero-aromatics; 1.4x10-3 - 1.52 and 1.3x10-3 - 1.23 for carbonyls. Similar trends observed for the experimental values of Δµ and Δα indicated that the more a transition is allowed, the greater the probability Δµ being larger than zero. The positive values of Δµ (5.7x10-3 - 1.73D) and Δα (8.0x10-5 - 5.5Å3) for hetero-aromatics; Δµ (3.7x10-2 - 1.23D) and Δα (4.8x10-4 - 0.95Å3) for carbonyls indicated substantial redistribution of the π-electron densities in more polar excited state than the ground state. The ΔELUMO-HOMO were (3.19 - 4.09eV) and (4.36 - 5.43eV) for carbonyls and hetero-aromatics respectively. The IP and ƞ increased as solvent polarity increased, suggesting high stability of these compounds in polar solvents. The modified equation is better in the estimation of transition dipole moment and transition polarizability. The energy gaps and associated parameters suggested strong activity of the molecules and minimal overlapping of the transition bands. 1 results 1
- ASME 1 results 1
- Academic and administrative responsibilities assigned to junior academic staff though crucial to their career growth, are largely becoming challenging and inimical to their overall career achievements in Nigeria. Previous studies on career growth in the Nigerian university system have concentrated more on remunerations, job satisfaction and commitment, staff welfare and incentives, funding and retention, organisational climate and career pathways without adequate consideration for the combined predictive effects of personal and work-related factors. Therefore, this study examined the combined prediction of personal (emotional intelligence and gender) and work-related (work attitude, administrative responsibility and mentoring) factors on junior academic staff career growth (Readiness for Promotion (RP), Number of Publications (NoP), Regular Class Attendance (RCA), Teaching Ability (TA) and Self-confidence (SC)) in universities in Southwestern Nigeria. The descriptive survey research design was adopted. Equal allocation method and stratified random sampling techniques were used to select 1200 junior academic staff from 12 purposively selected universities (four each from federal, state and private). Junior Academic Career Growth Scale (r=0.78), Administrative Responsibility (AR) Inventory (r=0.81), Work Attitude (WA) Scale (r=0.85), Emotional Intelligence (EI) Scale (r=0.82) and Mentoring Scale (r=0.81) were used for data collection. These were complemented with four sessions of in-depth interview with four randomly selected junior academic staff in each of the 12 institutions; making a total of 48 sessions. One research question was answered and six hypotheses tested at 0.05 level of significance. Data were subjected to Pearson product movement correlation, multiple regression and content analysis. Personal and work-related factors had a joint significant prediction on junior academic staff career growth (JASCG) (F(5,1194) =116.47) and jointly accounted for 33.0% of its variance. Emotional intelligence (β=0.355), gender (β=0.128), AR (β=0.074), WA (β=0.056) relatively contributed to JASCG, while mentoring did not. Also, EI (r=0.531), gender (r=0.430), mentoring (r=0.416), WA (r=0.326) and AR (r=0.224) positively correlated with JASCG. Administrative responsibilities significantly correlated with the components of JASCG as follows: TA (r=0.218), NoP (r=0.145), RCA (r=0.132), SC (r=0.130), and RP (r=0.115); while work attitude correlated with the same components as ranked: NoP (r=0.338), SC (r=0.369), RP (r=0.343), RCA (r=0.295) and TA (r=0.265). Further, EI correlated with JASCG components in this order: NoP (r=0.047), SC (r=0.025), TA (r=0.025), RCA (r= -0.56), RP (r=-0.34). Mentoring also correlated with JASCG as ranked: NoP (r=0.209), TA (r=0.146), SC (r=0.143), RCA (r=0.135), RP (r=0.112). The junior academic staff can always cope with the rigour of academics and constantly experience ease career growth without much hindrance under good work environment, flexible work system, better mentoring system and high level of intelligence. Administrative responsibilities, work attitude, emotional intelligence and gender positively predicted the career growth of junior academic staff in universities in Southwestern Nigeria. There is, therefore, the need for the university management to provide enabling work environment that can enhance the right work attitude and emotional stability of the junior academic staff for them to perform optimally. In addition, there is the need to ensure an effective formal mentoring system and reduction of excessive workload. 1 results 1
- Adjustment 1 results 1
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