537 research outputs found
Emphasizing Landscape Elements as Important Components of a Sustainable Built Environment in Nigeria
Many residential areas in the built environment in the developing countries with reference to Nigeria are generally unattractive and lack basic landscape elements. Landscape elements encompass both natural and artificial features used to create a befitting visual presentation within the built environment; as such its role cannot be overemphasized. In line with the ethos of sustainable development, sustainability is an important concept in today’s urban planning, as such landscaping can be used to play a revitalizing role in the continued depletion and degradation of the natural environment. This paper examines the poor state of many residential areas in the built environment in Nigeria and the impact on the physical outlook. It further discusses landscape elements and their use in the built environment and the benefits of landscaping to a sustainable built environment. Using a case study approach the study looks at two residential housing estates in Akure, Nigeria to ascertain the extent to which landscaping elements have been used. The case study established that landscaping elements do not exist in many parts of the estates and where there is, lack adequate maintenance. The paper concludes that landscaping plays a vital role in achieving a sustainable built environment and therefore need to be incorporated in the Nigerian built environment. Keywords: Built Environment, Landscape Elements, Landscaping, Sustainabilit
Short-Term Lime Pretreatment and Enzymatic Conversion of Sawdust into Ethanol
The utilization of lignocellulosic biomass as feedstock for the production of fuel ethanol has attracted considerable interests in the last few decades. The emergence of new technologies has provided hope for fuel ethanol potential uses. Lignocellulose is a valuable alternative energy source. The enzymatic hydrolysis of lignocellulosic biomass is constrained due to its complex structural features, so pretreatment is important to enhance its enzymatic digestibility. In this study, the influence of process parameters – temperature, air addition, hydrogen peroxide addition, and time – on the pretreatment of sawdust (a wood residue) was investigated. The optimization of the pretreatment step was performed by using the full factorial and central composite designs of experiments. The study assessed the compositional changes by applying short-term oxidative pretreatments such as alkaline wet air oxidation, alkaline peroxide oxidation, and alkaline peroxide assisted wet air oxidation methodologies, and their effects on the yields of reducing sugar. The best pretreatment condition based on the yield of the reducing sugar was the alkaline peroxide-assisted wet air oxidation at 150 oC, 1%H2O2, 10 bar air pressure, 45 min. The optimal 4-day reducing sugar yield was 335.35 mg equivalent glucose/g dry biomass at 40 g/L substrate concentration, 25 FPU/g dry substrate of cellulase enzyme, and 5 IU/g dry substrate of β-glucosidase. Furthermore, when considering the fermentability of the treated solids, at 2% effective cellulose loading, 9.71 g/L ethanol (23.43% theoretical ethanol yield) was obtained for pretreatment at 150 oC, 1%H2O2, 10 bar air pressure, and 45 min. At the optimum pretreatment condition, 0.1 g Ca(OH)2/g dry biomass was enough to cause appreciable lignin removal. Lignin removal was largely dependent on temperature, and the prevailing oxidative conditions. Cellulose was highly preserved in the solid fraction, while more of the hemicellulose was solubilized/degraded. The high-lignin content of the raw material was a great obstacle to the digestibility of the treated material. The lignin remained largely undissolved in the solid fractio
A study of the kinetic of synthesis and crosslinking of methylol melamine
One mole of melamine (2,4,6 – amino 1,3,5 – triazine), approximately 126 g were reacted separately in suitable beakers on hot plate with stirrer using 144 cm3, 216 cm3, 288 cm3 , 360 cm3 and 432 cm3, of 37% formaldehyde which is equivalent to 2, 3, 4, 5 and 6 moles respectively. The reaction was carried out in the presence of little quantity sodium dihydrogen phosphate as a catalyst, at various temperatures, molar ration of the reactants and concentration of catalyst. Since melamine is hexafunctional, complete formylation produces up to hexamethylol derivative before crosslinking take place. The kinetic of the reaction were affected by varying these parameters but follows a none complicated form. The relative viscosity of each resin increase as concentration increases. Increase in the amount of catalyst used and temperature of reaction medium reduced the time of formation and subsequent crosslinking to the resins.Keywords: Kinetic, Synthesis, Melamin
Empirical Investigation into Industrial Relations and National Productivity in Nigeria
This paper investigated the impact of the poor industrial relations on the National productivity in Nigeria. The paper is a contribution to the often debated issue of privatization of the proliferated public parastatals. In the study, time series data over the period 1970 – 2004 was used and the modified Least Square was employed as analytical tool. The study found that trade disputes and work stoppages negatively affect the growth of national productivity; proxied by per capita income. Evidence also suggests that the shock received by the economy through trade disputes is mostly felt in subsequent year – a phenomenon known as J – Curve. The policy implication of the study was that government should seek possible ways to improve workers productivity especially in those establishments and parastatals which can not be privatized. Keywords: Industrial Relations, Productivity, Nigerian Econom
Communal Facilities and Residential Neighbourhoods in Akure, Nigeria
Availability of communal facilities within the neighbourhoods helps to meet various social needs. At the same time satisfies current needs of the local communities without exerting strain on the existing facilities to the detriment of future demand. The focus of this paper is on communal facilities in selected residential estates in Akure, the capital city of Ondo state, Nigeria. Using the primary and secondary sources of data collection, the paper takes a critical look at the importance of communal facilities in neighbourhoods and examines the adequacy of communal facilities in residential areas in Nigeria. Two residential estates in Akure namely: Alagbaka and Ijapo estates were studied through the use of questionnaire and direct observations, to elicit relevant data relating to social, economic and environmental variables. Data obtained were collated and findings from empirical survey presented in the single factor descriptive analysis. Findings from the study affirm that the communal facilities available within the study area were inadequate. The paper recommends public enlightenment, environmental education, upgrading of existing facilities to acceptable standard. Keywords: Communal Facilities, Neighbourhood, Residential Estates, Housin
Investigating the Relevance of Cultural Landscapes in Tourism Experience in Abeokuta
Tourism is a modern global phenomenon, and the synergy between this phenomenon and cultural landscapes has increased the demand at both local and international levels. This paper investigates the relationship between cultural landscape and tourism, especially in Abeokuta, Ogun State. This is on the premise of bringing about sustainable development in tourism, thereby enhancing the cultural and economic values of the site. The study is important as it provides a medium for the assessment of Abeokuta cultural landscapes, and relates the influencing factors with the assessment results. This was carried out through a critical review of existing literature on cultural landscapes and the inseparable link with tourism, as well as an empirical investigation using the quantitative method of data collection through questionnaire survey on all stakeholders in the tourism industry in Abeokuta. The data generated from the survey were analyzed and results were expressed in percentages. The findings revealed that cultural landscapes actually have a positive input regarding sustainable development, and also have immense contributions towards the wellbeing of man. It also brought to limelight, the factors contributing to the quality of landscapes in Abeokuta. The paper therefore strongly recommends that adequate information should be made available to all stakeholders to improve their interest and participation, which brings about effective management, and subsequently, sustainable tourism. Keywords: Cultural Landscape, Abeokuta, Sustainable Tourism, Tourists Sites. DOI: 10.7176/JTHS/55-04 Publication date:March 31st 202
Optimization of enzymatic digestibility of sodium hydroxide- hydrogen peroxide oxidative pretreated siam weed for reducing sugar production
This study evaluated the enzymatic conversion of alkaline peroxide oxidative pretreatment of an invasive lignocellulosic biomass (siam weed) to reducing sugar, amenable to further microbial effects at the downstream processing. Using a statistical design of experiments approach (response surface methodology), optimum pretreatment conditions of 43.7 oC, 9.3 h, and 0.4% H2O2 , and enzymatic hydrolysis conditions of 25 FPU cellulase/g treated biomass, 50 oC hydrolysis temperature, 2% biomass loading, and 72 h hydrolysis period, 391.3 mg/g reducing sugar yield was achieved and validated. At the optimized pretreatment and enzymatic conditions, the conversion of treated biomass to untreated biomass was about a 6-fold increase
Effective Gravimetric Characterization for Lignocellulosic Biomass: Comparison of NaOH-H2O2 and Ca(OH)2-H2O2 Oxidation Pretreated Sugarcane Bagasse
In this study, alkaline peroxide oxidation
pretreatment was evaluated for sugarcane bagasse, a
lignocellulosic biomass. By comparing the effects of NaOHH2O2
and Ca(OH)2 on pretreatments at specified reaction time
periods (3, 6, 9, and 12 h) and reaction temperatures (60, 70,
80, and 90 h), optimum responses in term of cellulose content,
hemicellulose solubilization, and lignin removal were
established. Optimum pretreatment conditions of 80 oC
reaction temperature, 3 h reaction time, and 30 mL/L of water
hydrogen peroxide concentration (1%H2O2) solubilized
69.5%(w/w) hemicellulose for the sodium hydroxide peroxide
(SHP) pretreatments, 75.8%(w/w) lignin removal was also
achieved with 59.2%(w/w) cellulose retained in the solid
fraction. In addition, the responses for the optimum
conditions for the calcium hydroxide peroxide (CHP)
pretreatments, the cellulose content, hemicellulose
solubilization, and lignin removal were 50.3%, 66.6%, and
65.4%(w/w) respectively. Pretreatments showed both NaOHH2O2
and Ca(OH)2-H2O2 to be useful pretreatment agents for
the disruption of the polysaccharide complex. The study also
revealed that NaOH-H2O2 pretreatment stands as a better
choice to Ca(OH)2-H2O2 pretreatment
Strategies for Mitigating Building Collapse in Nigeria: Roles of Architects and Other Stakeholders in the Building Industry
Collapse of buildings is one of the several failures of building projects and results either in loss of lives, properties and in some cases both. Often times the professionals in the building industry made up of Architects, Engineers, Planners, Quantity Surveyors, Land Surveyors, Estate Surveyors, Town Planners, Builders and Project Manager trade blames on who should be held responsible for the failure. Many factors can be adduced to the continuous occurrences of building collapse which, include inadequate monitoring of construction sites by government officials as a result of the vast and fast pace of developments in many Nigerian urban centres; as well as the use of substandard materials, improper soil investigations, bad design and supervision, poor quality construction and poor funding by clients. Using the secondary source of data collection, the paper discusses the roles the architect could play both in practice and in architectural education in mitigating building collapse. Findings reveal that mitigation of building collapse can be achieved in Nigeria through collaborative efforts of all stakeholders involved and concludes that architectural education could serve a supportive role. Keywords: Architects, Architectural Education, Building Collapse, Mitigation, Nigeri
Comparison of ViTEK 2, MALDI-TOF and Partial Sequencing of 16S rRNA Gene in Identification of Brevibacterium Species with its Antibiotic Susceptibility Pattern
Background - Brevibacterium species were formerly viewed as apathogenic, however, recent reported cases of infectious states caused by Brevibacterium sp. have renewed interests in the genus as infectious agents. However, several authors have reported difficulties in identification of different species in the genus and resistance to some antibiotics.Objectives – This study is therefore designed to compare accuracies of 3 methods for identification of Brevibacterium spp. and their antibiotic susceptibility pattern.Methods – Ten Brevibacterium spp. were presumptively identified from staphylococci collections due to their characteristic cheesy smell. The selected isolates were identified by MALDI TOF, Vitek 2 identification system and partial sequencing of 16S rRNA gene by standard procedures. The antibiotic susceptibility was determined by disc diffusion method.Results - Vitek 2 identification system misidentified all the organisms while MALDI TOF identification system correctly identified the Brevibacterium strains to the genus level but with scores less than 1.7 for all tested strains. 16S rRNA identification identified the 10 strains as 3 species: 5 B. epidermidis, 3 B. iodinum and 2 B. oceani. All the strains were susceptible to Vancomycin, Linezolid and Rifampicin while they were all resistant to Penicillin, Fusidic acid, and Trimethoprim. Brevibacterium epidermidis were generally resistant to Erythromycin and Clindamycin while B. iodinum and B. oceani were susceptible.Conclusion - 16S rRNA identification is the only method that could correctly identified Brevibacterium sp to the species level in this study. High susceptibility was shown by all tested strains to Vancomycin, Linezolid and RifampicinKeywords – Brevibacterium, Identification, Antibiotic susceptibilit
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