114 research outputs found
LCS Tool : A Computational Platform for Lagrangian Coherent Structures
We give an algorithmic introduction to Lagrangian coherent structures (LCSs)
using a newly developed computational engine, LCS Tool. LCSs are most
repelling, attracting and shearing material lines that form the centerpieces of
observed tracer patterns in two-dimensional unsteady dynamical systems. LCS
Tool implements the latest geodesic theory of LCSs for two-dimensional flows,
uncovering key transport barriers in unsteady flow velocity data as explicit
solutions of differential equations. After a review of the underlying theory,
we explain the steps and numerical methods used by LCS Tool, and illustrate its
capabilities on three unsteady fluid flow examples
Non-Monetary Motivation Strategies and Growth of Selected Deposit Money Banks in Ogun State, Nigeria
The challenge facing managers in the banking sector is how to get employees committed to their work and put in their best towards the accomplishment of banks’ goals and objectives. There was gradual and consistent decline in the performance of banks due to low level of motivation within and outside the banking organizations. It is therefore imperative for managers in the banking sector to design and implement strategies and policies that will adequately address issues relating to employees’ welfare so that it will help in achieving industrial peace which is a panacea to organizational growth. The general objective of this study was to establish the effect of non-monetary motivational strategies on the growth of selected deposit money banks in Ogun State, Nigeria. The study adopted cross-sectional survey and target population was 800 staff of the selected commercial banks in Ogun State and sample of 481 employees was used in this study. A stratified sampling technique method was used and data was collected through the use of questionnaire. A pilot study was conducted to pretest the validity and reliability of instruments for data collection. The data was analyzed by use of quantitative method with the help of Statistical Package for Social Sciences (SPSS) version 21.0. The study established that work environment, leadership style, training and career advancement have positive and significant effect on the growth of selected deposit money banks in Ogun State, Nigeria. The regression analysis showed that work environment plays the most significant role on the growth of selected deposit money banks in Ogun State at 5% level of significance. Based on these findings, the study recommended that management of selected deposit money banks in Ogun State should plan very well when considering motivational strategies aimed at increasing overall productivity of the workers so as to achieve growth. Keywords: Motivation strategies, Leadership style, Training, Work environment, Growt
Kinetics and mechanistics steps to the electron transfer reaction of peroxo-bridged binuclear cobalt(III) complex of succinimide by glycine in aqueous acidic medium
ABSTRACT. The kinetics and mechanistic steps to the electron transfer reaction of the peroxo-bridged binuclear cobalt(III) complex of succinimide [(suc)(en)2Co(O2)Co(en)2(suc)2+] hereafter called peroxo-bridged dicobalt(III) complex ‘[Co(O2)Co2+]’ by glycine have been carried out spectrophotometrically at λ = 420 nm and T = 26 ± 1 oC, [H+] = 1 x 10-3 M and ᶙ = 0.5 M (NaCl) in aqueous acidic medium. The reaction was found to be first order with respect to [Co(O2)Co2+] and [(Gly] and experimental data indicates a second-order overall. The reactions obeyed the general rate law: (d[Co(O2)Co2+]/dt) = (a +b)[H+])[Co(O2)Co2+][Gly]. Varying hydrogen ion concentration accelerated the reaction rate and shows first-order dependence while the reactions also affected by changes in the ionic strength of the reaction medium by giving a non-negative salt effect in the course of the reaction. Free radicals were not detected in the reactions. Spectroscopic investigation and Michaelis-Menten plots suggest the absence of intermediate complex formation. The experimental result obtained in this system is concluded in favor of the outer-sphere mechanism.
KEY WORDS: Cobalt(III) complex, Kinetic, Electron transfer, Spectroscopic, Mechanistic steps, Michaelis-Menten, Glycine
Bull. Chem. Soc. Ethiop. 2021, 35(2), 425-434.
DOI: https://dx.doi.org/10.4314/bcse.v35i2.1
Impact of Agricultural Waste on Sustainable Environment and Health of Rural Women
The study worked on the impact of agricultural waste on sustainable environment and health of rural women. Three specific objectives were formulated for the study and included to identify the constituents of agricultural waste, to determine the environmental and health impact of agricultural waste and to determine the effective management techniques of agricultural wastes. Three research questions and three null hypotheses were also formulated in line with the specific objectives. Survey research design was adopted for the study. Population for the study was 3970 representing 450 registered livestock farmers, 3270 rural women and 250 environmental health workers in Anambra State. Proportionate random sampling technique was used to draw a sample of 350 respondents representing 40 registered livestock farmers, 286 rural women and 24 environmental health workers. Questionnaire developed by the researchers was used to collect data. The instrument was face validated by three experts and reliability was tested using cronbach alpha method which yielded a coefficient of 0.86. Data were collected with the help of fifteen research assistants and 325 instruments were retrieved representing 81% return rate. Mean and Standard Deviation were used to answer the research questions while ANOVA was used to test the null hypotheses at 0.05 level of significance and at the appropriate degrees of freedom. Any null hypothesis whose p-value was greater than 0.05 level of significance at the appropriate degrees of freedom was upheld while a null hypothesis was rejected when the p-value was less than 0.05 level of significance at the appropriate degrees of freedom. The findings of the study indicated that animal faeces, urine, used litter, beddings, animal carcass, dairy parlor washings, waste milk, wasted feed, feedlot run-off, paunch waste, abattoir waste water, animal viscera, horns, feather, bones, blood, fur, placenta, birth tissues, fetal membranes, aborted fetus among others are the materials that constitute agricultural waste. It was also found that that air pollution from burning of agricultural wastes, air pollution from cesspools, dioxins from burning agricultural wastes, dirty environment from heaps of agricultural wastes, stench/odour from decaying agricultural waste, defacing of the environment, eutrophication of water bodies, aquatic life destruction, spontaneous abortion, blue-baby syndrome, prolonged mensuration and early menopause, among others are the environmental and health impact of agricultural waste on rural women. It was recommended among others that Extension workers should properly educate farmers on the dangers of agricultural wastes and sensitize them on proper disposal methods. Keywords: agricultural waste, environment, health, rural women, pollution
Survey on Sample Sizes of Postgraduate Theses in Agricultural Education and Extension in Universities of Nigeria
The study focused on the representativeness of the sample sizes generated for populations under study in survey studies in Agricultural Education and Agricultural Extension. The study was carried out in Nigeria. A total of 4561 completed survey theses submitted to the Departments of Agricultural Education and Agricultural Extension in federal universities in Nigeria for the award of various postgraduate degrees between 2008 and 2018 were studied. The objectives of the study were to report the effect of sample size on the confidence level and margin of error of the generated data and to determine the frequently cited formula for generating sample sizes and their implications. The most frequently cited method for generating sample sizes was reported. Findings further revealed the problems associated with using nonstatistical methods to generate sample sizes. The study recommended the use of mathematically proven formula in determining sample sizes in survey studies to generate statistically dependable, reliable and generalizable data
Feijão guandu cru na alimentação de frangos caipiras criados em sistema semi-intensivo
Density measurements using the Background Oriented13; Schlieren technique
This paper describes the implementation of a13; novel technique called Background Oriented Schlieren that13; can produce quantitative visualization of density in a flow.13; This technique uses only a digital still camera, a structured13; background, and inverse tomographic algorithms which13; can extract two-dimensional slices from a three-dimensional13; flow. This has been applied to obtain the density13; field for an axisymmetric supersonic flow over a conecylinder13; model. Comparisons with cone tables show13; excellent agreement
Comparative Study on Quality of Fuel Pellets from Switchgrass Treated with Different White-Rot Fungi
Fungal pretreatment of switchgrass using Phanerochaete chrysosporium (PC), Trametes versicolor 52J (TV52J), and the Trametes versicolor mutant strain (m4D) under solid-state fermentation was conducted to improve its pellet quality. For all three fungal strains, the fermentation temperature had a significant effect (p < 0.05) on pellet unit density and tensile strength. The p-values of the quadratic models for all the response variables showed highly significant regression models (p < 0.01) except for dimensional stability. In addition, 3.1-fold and 2.8-fold increase in pellet tensile strength were obtained from P. chrysosporium- and T. versicolor 52J-treated materials, respectively. Microstructural examination showed that fungal pretreatment reduced pores in the pellets and enhanced pellet particle bonding. Among the fungal strains, PC had the shortest optimum fermentation time (21 d) and most positive impact on the pellet tensile strength and hydrophobicity. Therefore, switchgrass pretreatment using PC has the potential for resolving the challenges of switchgrass pellet transportation and storage and reducing the overall pelletization cost. However, a detailed comparative technoeconomic analysis would be required to make definitive cost comparisons
Optimization of Solid-State Fermentation of Switchgrass Using White-Rot Fungi for Biofuel Production
Biological delignification using white-rot fungi is a possible approach in the pretreatment of lignocellulosic biomass. Despite the considerable promise of this low-input, environmentally-friendly pretreatment strategy, its large-scale application is still limited. Therefore, understanding the best combination of factors which affect biological pretreatment and its impact on enzymatic hydrolysis is essential for its commercialization. The present study was conducted to evaluate the impact of fungal pretreatment on the enzymatic digestibility of switchgrass under solid-state fermentation (SSF) using Phanerochaete chrysosporium (PC), Trametes versicolor 52J (Tv 52J), and a mutant strain of Trametes versicolor that is cellobiose dehydrogenase-deficient (Tv m4D). Response surface methodology and analysis of variance (ANOVA) were employed to ascertain the optimum pretreatment conditions and the effects of pretreatment factors on delignification, cellulose loss, and total available carbohydrate (TAC). Pretreatment with Tv m4D gave the highest TAC (73.4%), while the highest delignification (23.6%) was observed in the PC-treated sample. Fermentation temperature significantly affected the response variables for the wild-type fungal strains, while fermentation time was the main significant factor for Tv m4D. The result of enzymatic hydrolysis with fungus-treated switchgrass at optimum pretreatment conditions showed that pretreatment with the white-rot fungi enhanced enzymatic digestibility with wild-type T. versicolor (52J)-treated switchgrass, yielding approximately 64.9% and 74% more total reducing sugar before and after densification, respectively, than the untreated switchgrass sample. Pretreatment using PC and Tv 52J at low severity positively contributed to enzymatic digestibility but resulted in switchgrass pellets with low unit density and tensile strength compared to the pellets from the untreated switchgrass
Discussion of "Buckling of a weakened column" by C. Y. Wang, C. M. Wang, and Tun Myint Aung
10.1061/(ASCE)0733-9399(2005)131:12(1329)Journal of Engineering Mechanics131121329-133
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