Browsing by Title
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Meck, M.L.; Atlhopheng, J.; Masamba, W.R.L.; Ringrose, S.; Diskin, S. (Bentham Open, http://www.benthamscience.com/open/tomj/index.htm, NaN, 2011)[more][less]
Abstract: This study set out to establish the major minerals at Dorowa and determine which of those are likely to host metals that may leach into surface and groundwater. This study comes after a preliminary assessment of the water quality in the Save River downstream of the Dorowa phosphate mine in Zimbabwe showed an increase in conductivity, iron content, manganese content, nitrates and hardness when compared to those taken before the mining area. X-Ray Diffractometry (XRD) was used to establish the major minerals at Dorowa whilst Inductively Coupled Plasma Mass Spectrometry (ICP- MS) was used to establish the chemistry of the rocks. The results from this study show that the major minerals in the rocks around Dorowa are feldspars, pyroxenes, apatite, magnetite and calcite. The metals hosted by the rocks include Ag, As, Be, Cd, Co, Cu, Pb, Hg, Ni, Sb, Se and Zn. The study concludes that the minerals likely to host metals are calcite and apatite. Metal hosting is higher in apatite minerals than in calcite. Metal hosting by the other minerals observed in the study area is low. URI: http://hdl.handle.net/10311/1109 Files in this item: 1
Atlhopheng_OMJ_2011.pdf (848.6Kb) -
Meck, M.; Atlhopheng, J.; Masamba, W.; Ringrose, S.; Diskin, S. (Bentham Open, NaN, 2010)[more][less]
Abstract: This study set out to establish the major minerals at Dorowa and determine which of those are likely to host metals that may leach into surface and groundwater. This study comes after a preliminary assessment of the water quality in the Save River downstream of the Dorowa phosphate mine in Zimbabwe showed an increase in conductivity, iron content, manganese content, nitrates and hardness when compared to those taken before the mining area. X-Ray Diffractometry (XRD) was used to establish the major minerals at Dorowa whilst Inductively Coupled Plasma Mass Spectrometry (ICP- MS) was used to establish the chemistry of the rocks. The results from this study show that the major minerals in the rocks around Dorowa are feldspars, pyroxenes, apatite, magnetite and calcite. The metals hosted by the rocks include Ag, As, Be, Cd, Co, Cu, Pb, Hg, Ni, Sb, Se and Zn. The study concludes that the minerals likely to host metals are calcite and apatite. Metal hosting is higher in apatite minerals than in calcite. Metal hosting by the other minerals observed in the study area is low. URI: http://hdl.handle.net/10311/932 Files in this item: 1
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Mgadla, P.T. (Research and Development Unit, University of Botswana, NaN, 1997)[more][less]
Abstract: This paper is about the introduction of western education by Missionaries in Africa. These European Missionaries left their homes for religius reasons, to convert the "heathens" to the christian religion. Convertion to christian religion faced many hurdles like language barriers, cultural beliefs and that the people to be converted were illiterate. The converts to be had to be taught how to read and write to be able to interpret the bible. The education offered by Missionaries was tended to be scriptural in nature because the intended converts were supposed to read and understandthe great book of God - the Bible. Emphasis was on religious studies. Missionaries targeted African leaders such as Chiefs in their endeavor to convert and also to introduce western education. Once the leaders were convinced and converted in the new religion and education, they would influence the dissemination of the new faith to their groups or tribes. Western education was introduced in the manner such as described above among Batswana. The Missionaries who introduced western education and christianity were members of the London Missiory Society (LMS) formed in 1795 and these were Dr. Robert Moffat and Dr. Livingstone. URI: http://hdl.handle.net/10311/475 Files in this item: 1
Mgadla_PJAS_1997.pdf (827.3Kb) -
Malumbela, G.; Alexander, M.; Moyo, P. (Elsevier http://www.elsevier.com/locate/conbuildmat, NaN, 2011)[more][less]
Abstract: Cracking of the cover concrete due to steel corrosion is considered by many researchers to indicate the end-of-service life of corrosion-affected reinforced concrete (RC) structures. Numerous models have been developed to predict the time from corrosion initiation to cracking of the cover concrete. In the previous models, concrete with corroding steel bars was assumed to behave like a thick-walled cylinder under uniform internal pressure. Recent research publications have however, shown that steel corrosion is often concentrated on the surface of the steel that faces the direction of ingress of corrosion agents. This paper presents a model that relates the level of partial surface steel corrosion with the transverse and vertical strains measured on the exterior faces of corrosion-affected RC beams. The model assumes that the remaining section of the steel after corrosion is elliptical shaped. Finally, the model is calibrated with experimental data in the literature and it is shown that assuming uniform steel corrosion underestimates the internal pressure applied by the expansive corrosion products. URI: http://hdl.handle.net/10311/682 Files in this item: 1
Malumbela2_CBM_2011.pdf (481.3Kb) -
Marumo, R.; Tokhi, M.O. (University of Botswana, Faculty of Engineering and Technology, http://ajol.info/index.php/bjt, April NaN, 2007)[more][less]
Abstract: This article proposes a new modeling scheme using extended radial basis function (RBF) and adaptive neuro-fuzzy filter for handling nonlinear uncertainties of an air motor servo valve. This model combines the fast model development ability of RBF and the adaptation capability of adaptive neuro-fuzzy inference system (ANFIS) used instead of the well known conventional modeling techniques. The ANFIS structure provided parameter partitioning and better performance under transient response to handle the problem of disturbance attenuation. The pneumatic H-bridge, characterizing a pneumatic servo valve has been devised for speed and direction control of the motor and the system characteristics conveniently divided into three main regions; of low speed (below 390 rev/min), medium speed (390 to 540 rev/min) and high speed (540 to 680 rev/min). The system is highly non-linear in the low speed region and hence the need to use an adaptive intelligent based modeling technique arises. Simulation results has proven that for an air motor system with uncertainty and perturbed noise, the RBF-ANFIS model scheme performed well and out past its conventional counterpart by far. URI: http://hdl.handle.net/10311/657 Files in this item: 1
Marumo_BJT_2007.pdf (5.657Mb) -
Temtime, Z.T. (Emerald; http://www.emeraldinsight.com/0954-478x.htm, NaN, 2003)[more][less]
Abstract: Total quality management (TQM) research has concentrated on large firms. Little has been done on the TQM practices of small- to medium-sized enterprises (SMEs), particularly in developing countries. This paper investigates the relationship between TQM, planning behaviour and firm size by reviewing existing literature and collection of primary data from 54 SMEs in the Republic of Botswana. The findings indicated that the majority of SMEs understand the importance of both TQM and planning activities for their survival and growth. However, their approach to both is unsystematic, non-formal and short-term orientated. Both firm size and planning behaviour are found to have statistically significant relationships with TQM practices. As firm size increases from small to medium, and as SMEs move from operational to strategic planning, they attach greater degree of importance to TQM practices. However, the planning behaviour of SMEs is more strongly related to TQM practices as a prerequisite to the adoption of formalised TQM practices. Some implications for SMEs are also forwarded. URI: http://hdl.handle.net/10311/193 Files in this item: 2
license.txt (1.998Kb)temtime_TQM_2003.pdf (2.598Mb) -
Togarasei, L. (Brill Academic Publishers, NaN, 2005)[more][less]
Abstract: The past twenty to thirty years in the history of Zimbabwean Christianity have witnessed the emergence of a new breed of Pentecostalism that tends to attract the middle and upper classes urban residents. This paper presents findings from a case study of one such movement, the Family of God church. It describes and analyses the origins, growth and development of this church as an urban modern Pentecostal movement. The first section of the paper discusses the origins and development of the church focusing on the life of the founder. The second section focuses on the teaching and practices of the church. The church’s doctrines and practices are here analysed to find out the extent to which these have been influenced by the socio-political and economic challenges in the urban areas. The paper concludes that the modern Pentecostal movement is meant to address urban needs. URI: http://hdl.handle.net/10311/598 Files in this item: 1
Togarasei_E_2005.pdf (251.2Kb) -
Matsheka, M.I.; Lastovica, A.J.; Elisha, B.G. (American Society for Microbiology. http://jcm.asm.org/, NaN, 2001)[more][less]
Abstract: A 1.6-kb DNA fragment isolated from a Campylobacter concisus genomic library gave C. concisus-specific restriction fragment length patterns when it was used as a probe in hybridization studies. All of the strains tested, including type strains and clinical isolates, contained a 0.5-kb HindIII fragment that hybridized to the probe. DNA sequencing of the 1.6-kb fragment identified three open reading frames (ORFs). One of the ORFs encodes the carboxy terminus of GyrB, and the translational products of ORF2 and ORF3 showed similarity to hypothetical proteins, previously identified in Campylobacter jejuni. DNA-DNA hybridization studies with a fragment internal to ORF3 showed that this sequence was responsible for the signal observed with the 0.5-kb HindIII fragment. A rapid PCR assay was developed and evaluated. Primers that annealed to the extremities of the 1.6-kb fragment were used to obtain an amplicon of the correct size from both reference and clinical strains of C. concisus. URI: http://hdl.handle.net/10311/306 Files in this item: 1
Molecular identification of.pdf (4.701Mb) -
Mark, M. (University of Botswana, http://ub.bw, NaN, 2007)[more][less]
Abstract: Botswana is facing one of its greatest development challenges at the moment. It is facing an HIV/AIDS pandemic of immense proportions. It is among the countries in the world that have been hard hit by this scourge. A lot of stakeholders including government, private companies, international donor agencies, and civil society have come up with interventions to respond to challenge of fighting this pandemic. Among the key players in this fight against HIV/AIDS are civil society organizations, commonly known as NGOs. These organizations play a crucial role of bringing HIV/AIDS services to the communities where the other players may not reach or may not be effective. The services the NGOs offer to communities are normally delivered as projects. Effective monitoring and evaluation of projects is usually one of the ingredients of good project performance and provides means of accountability, demonstrating transparency to the stakeholders and facilitates organizational learning for benefit of future projects. This study sought to determine how effectively the HIV/AIDS projects implemented by Gaborone based local NGOs are monitored and evaluated. The study investigated the monitoring and evaluation practices of the NGOs and compared them with the best practices. It also sought to identify the challenges the NGOs faced in carrying out this function. Data for the study was collected using the descriptive survey method where a questionnaire was administered to project managers and monitoring and evaluation officials of the NGOs. The results of the study show that most of the NGOs (66.7%) were implementing Behavioral Change Communication projects. The study also determined that the monitoring and evaluation practices of the local NGOs fell short of the best practices. Most of the best practices were inconsistently done and others were not done at all. Planning for monitoring and evaluation was inadequately done and inconsistently by respondents. Implementing the monitoring and evaluation process was not effectively done by the respondents. The study also identified quite a number of challenges the NGOs faced in carrying out monitoring and evaluation of the projects they faced. These challenges made it hard for the NGOs to effectively monitor and evaluate the projects they implemented. The most significant ones included; inadequate finances, lack of expertise, stringent and multi-donor reporting requirements, lack of baseline data. The study made some recommendations in order to mitigate the challenges faced by the NGOs. The study found out that, all in all the projects implemented by the local NGOs were not effectively monitored and evaluated. URI: http://hdl.handle.net/10311/991 Files in this item: 1
Mark-MEPC_2007.pdf (7.970Mb) -
Temtime, Z.T. (International Journal of Globalisation and Small Business; Inderscience Enterprises Ltd; http://www.inderscience.com/browse/index.php?journalCODE=ijgsb, NaN, 2006)[more][less]
Abstract: The process of gathering and interpreting pertinent information from the environment and introducing the results into the business planning process is referred to as environmental scanning. This paper investigates the practices and perceptions of Small and Medium Enterprises (SMEs) in monitoring environmental complexities and changes through the use of different scanning sources and frequency. Data were collected from 44 SMEs in Botswana through questionnaire and analysed using simple descriptive statistics. The findings indicated that SMEs in Botswana do monitor their environment and use all the major scanning sources with different degrees of frequency. Though more importance is attached to the customer/market, competition and economic sectors, owner-managers in Botswana tend to rely more on impersonal (written) and internal sources as opposed to personal (informal) and external sources to analyse an increasingly uncertain sector. This is in contrast to previous findings, since information from these sources is less reliable for analysing unstable, turbulent and hard-to-measure sectors than personal and external sources. The use of inappropriate scanning sources could be partially attributed to the fact that most SMEs in Botswana do not have an integrated management information system designed to capture, store and analyse environmental data for use in strategic decision-making processes. Further implications for SMEs and future research are highlighted. URI: http://hdl.handle.net/10311/49 Files in this item: 2
license.txt (1.998Kb)temtime_ijgsb_2006.pdf (157.1Kb) -
Mogobe, K.D.; Tshiamo, W.; Bowelo, M. (Reproductive Health Matters. www.rhmjournal.org.uk, NaN, 2007)[more][less]
Abstract: This paper describes the maternity monitoring system in Botswana, developed in 1998, and the main methods used: maternal death and morbidity reviews at service delivery level, analysis by the National Maternal Mortality Audit Committee of data from the reviews as reported on two forms, perinatal reviews and surveys using process indicators. We carried out a study of these findings to examine whether the system was working well. Surveys using process indicators in 2001 and 2006 were analysed. Other data examined were from 2004–2006 and early 2007. The Maternal Death Notification Form was found to be comprehensive but not all health facilities were submitting them and some gave incomplete information. In 2001, 70% of pregnant women attended antenatal care but access to emergency obstetric care was uneven. In 2006, 28 facilities with maternity services surveyed were providing 24-hour delivery care, but laboratory, theatre and blood supplies were more limited, and only 50% of doctors and 67% of midwives had life-saving skills. Antibiotics were widely available, but there were shortages of magnesium sulphate, diazepam, oxytocics and manual vacuum aspiration kits. Recommendations for improvements have been made, training for skilled attendants is ongoing and a medical school has just opened at the University of Botswana. A2007 Reproductive Health Matters. All rights reserved. URI: http://hdl.handle.net/10311/541 Files in this item: 1
Monitoring maternity.pdf (1.714Mb) -
Mogobe, K.D.; Tshiamo, W.; Bowelo, M. (Elsevier, www.rhmjournal.org.uk, NaN, 2007)[more][less]
Abstract: This paper describes the maternity monitoring system in Botswana, developed in 1998, and the main methods used: maternal death and morbidity reviews at service delivery level, analysis by the National Maternal Mortality Audit Committee of data from the reviews as reported on two forms, perinatal reviews and surveys using process indicators. We carried out a study of these findings to examine whether the system was working well. Surveys using process indicators in 2001 and 2006 were analysed. Other data examined were from 2004–2006 and early 2007. The Maternal Death Notification Form was found to be comprehensive but not all health facilities were submitting them and some gave incomplete information. In 2001, 70% of pregnant women attended antenatal care but access to emergency obstetric care was uneven. In 2006, 28 facilities with maternity services surveyed were providing 24-hour delivery care, but laboratory, theatre and blood supplies were more limited, and only 50% of doctors and 67% of midwives had life-saving skills. Antibiotics were widely available, but there were shortages of magnesium sulphate, diazepam, oxytocics and manual vacuum aspiration kits. Recommendations for improvements have been made, training for skilled attendants is ongoing and a medical school has just opened at the University of Botswana. URI: http://hdl.handle.net/10311/498 Files in this item: 1
DintleMogobe2007Mortality.pdf (944.3Kb) -
Selolwane, O. (African Sociological Review, NaN, 2006)[more][less]
Abstract: The main thesis of this paper is that Botswana's opposition parties are accountable for their failure to provide the voting public with a meaningful alternative to the ruling Botswana Democratic Party. While conceding the explanatory importance of other factors such as resource capacity, this paper departs from conventional wisdom by focusing on the strategic and ideological weaknesses of the opposition parties. it argues that the opposition parties made a number of strategic errors which rendered them electorally unattractive before they could establish their legitimacy as contenders for government power. To break the monopoly of power that the ruling party has so far enjoyed, Botswana's opposition must transform itself into a meaningful competitor and government-in-waiting. To do that they must (a)demonstrate that they have a viable, alternative economic management strategy to better satisfy the interests of a diverse voting public and (b)develop broad based political strategies targeting the diverse voting public to build voter confidence in the capability of the party as a possible government. The ruling party's track record of four decades of sustained economic growth leaves a formidable challenge to the opposition. URI: http://hdl.handle.net/10311/761 Files in this item: 1
Selolwane_ASR_2002.pdf (1.586Mb) -
Moleele, N.M.; Ringrose, S.; Matheson, W.; Vanderpost, C. (ScienceDirect, www.sciencedirect.com, NaN, 2002)[more][less]
Abstract: the cattle-dominated grazing areas of Botswana. Bush encroachment species – for instance Acacia tortilis, A. erubescens, A. mellifera, Dichrostachys cinerea, Grewia flava, and Terminalia sericea –are increasing in cover and density around foci points (e.g. water points and kraals) at the expense of the grass cover. A number of factors have the effect of encouraging the germination and survival of bush encroachment species. The practice of cattle husbandry and continual shifting of foci points within grazing areas have resulted in the spread of the distribution of bush encroachment species across the country. This is evidenced by the potential extent of 37 000 km2 (6 4% of Botswana) of darkened and near infrared (NIR) reflective bush encroached areas in 1994. This paper suggests that specific management strategies should be adopted to help overcome the bush encroachment problem, which is causing a significant reduction in the extent of Botswana’s high quality rangeland. These strategies may vary from the enforced reduction of grazing intensity in areas identified as being heavily bush encroached to the selective management of opportunistic (communal) grazing in better quality predominantly grassland areas. Further work is however required to update this analysis and especially to consider trends since 1994–1995. While some work on the extent of woody cover and the further causes of bush encroachment is being undertaken under the SAFARI2000 project, more research is needed in specific areas to pinpoint causes and responses to the bush encroachment problem. URI: http://hdl.handle.net/10311/985 Files in this item: 1
Moleele_ et al_More_Woody_2002.pdf (3.119Mb) -
Monyatsi, P.P. (Kamla-Raj Enterprises, http://www.krepublishers.com, NaN, 2006)[more][less]
Abstract: Productivity is the buzzword in all organizations worldwide. Organizations, including schools are busy trying to enhance the productivity of their employees by introducing a number of interventions or incentives. One of the interventions that was introduced in education in Botswana was teacher appraisal, and one of its objectives was to motivate teachers to improve their performance. This paper is based on a combined quantitative/qualitative study that was carried out from a sample of 607 secondary school teachers in seventeen schools in the South Region of Botswana evaluating the effectiveness of the current appraisal process as carried out in secondary schools. It looks at how the process of teacher appraisal can motivate teachers to improve their performance of facilitating effective teaching and students’ learning. The study revealed that if carried out properly, the appraisal process can motivate the teachers to do more. URI: http://hdl.handle.net/10311/649 Files in this item: 1
Monyatsi_JSocSci_2006.pdf (767.7Kb) -
Iyanda, O.; Ojo, O.S. (Emarald Group Publishing Limited, www.emeraldinsight.com/, NaN, 2008)[more][less]
Abstract: Purpose- The purpose of this paper is to examine the motivation, and perceived effect of information and communication technology (ICT) adoption in Botswana organisations. While a conceptual model of the adoption process in developed countries has been studied, not much empirical studies have been undertaken.This paper is an attempt to bridge the gap. Specifically, the paper addresses five questions; What motivated organisations in Botswana in their decesion to adopt ICT in their operations? What factors, internal and external, influenced the adoption decision? Which sources did the organisations contact for information on the adoption of ICT? What is the relative importance of those influences/motivating factors and information sources? What are the perceived effects of adoption?Design/methodology/ approach-The study was carried out using a survey method. The main intrument is a personally administered questionnaire that was based on items obtained and adopted from literature. Data were collected from a judgement sample of 29 business and public sector establishment, drawn from nine towns and cities of Botswana. The respondent in each organization was either the IT manager or the chief executive. The initial stage of the adoption process is examined by identifying in the sample Botswana organizations, the internal and external proponents of the ICT doption process, the sources from which organizations seek technical information, their perceived relative importance in the process and the effect of adoption on orgaizations activities. Findings - The study found that ICT application in Botswana was still at an elementary stage, mainly communications and recordkeepings. In terms of motivation and influence, the competitive motive and internal sources of information and influence were dominant and that the overall effect of ICT adoption on several organizational activities was moderately positive Originality/value - The identification of the key sources of influence and information for the adoption of ICT helps ICT marketing companies to target their marketing efforts more specifically, and services offered limited to basic needes that are relevant to use which ICT is currently applied in Botswana. Widespread adoption of ICT has turned it into a kind of 'hygiene' factor rather than a 'motivator'. In spite of the positive effect adoption has on various activities of aadopting organisations, adoption benefits arre matched by similar benefits of competing organisations, thus conferring no competitive advantages. It is only in the absence of adoption that those organisations adopting enjoy such competitive advantage. URI: http://hdl.handle.net/10311/787 Files in this item: 1
motivation influences.pdf (2.479Mb) -
Amey, KA.A.; Forcheh, N.; Setlhare, K. (Dove Medical Press Ltd. www.dovepress.com/, NaN, 2012)[more][less]
Abstract: Background: Predictive models for mortality due to human immunodeficiency virus (HIV) disease as a result of opportunistic infections, such as tuberculosis and pneumonia, have been developed. Methods: The data are taken from the Statistics South Africa multiple causes of death data for 2006 and 2007, which is available for public use. The dataset was compiled from death notifications, and contains up to five causes of death as well as some demographic characteristics of the deceased. The logistic regression modeling framework was used to model the presence or absence of HIV disease, given the predictive variables. Results: The higher the number of causes listed, the higher the likelihood that HIV would be a cause, with the percentage of notifications of HIV listed increasing from under 2% when only one cause is listed to almost 15% when 4–5 causes are listed. When the logit model was fitted to the multiple cause of death model, it was found that individual demographics were good predictors of the likelihood that the death notification would have HIV as one of the causes of death. Although there are highly significant differences in the likelihood that people of different demographics would die from HIV, the predictive power of these demographic factors on their own is very low, especially when there is only a single cause of death mentioned. With the full multiple cause of death model, two-way interactions between tuberculosis, pneumonia, and other opportunistic infections were highly significant, and their inclusion lead to significant improvements in the predictive power of the model. URI: http://hdl.handle.net/10311/1071 Files in this item: 1
Forcheh_OAMS_2012.pdf (302.7Kb) -
Simbiri, K.O.; Murakami, M.; Feldman, M.; Steenhoff, A.P.; Nkomazana, O.; Bisson, G.; Robertson, E.S. (BioMed Central Ltd. www.infectagentscancer.com/content/5/1/6, NaN, 2010)[more][less]
Abstract: Background: Ocular surface squamous neoplasia (OSSN) is a rare cancer that has increased in incidence with the HIV pandemic in Africa. The underlying cause of this cancer in HIV-infected patients from Botswana is not well defined. Results: Tissues were obtained from 28 OSSN and 8 pterygia patients. The tissues analyzed from OSSN patients were 83% positive for EBV, 75% were HPV positive, 70% were KSHV positive, 75% were HSV-1/2 positive, and 61% were CMV positive by PCR. Tissues from pterygium patients were 88% positive for EBV, 75% were HPV positive, 50% were KSHV positive, and 60% were CMV positive. None of the patients were JC or BK positive. In situ hybridization and immunohistochemistry analyses further identified HPV, EBV, and KSHV in a subset of the tissue samples. Conclusion: We identified the known oncogenic viruses HPV, KSHV, and EBV in OSSN and pterygia tissues. The presence of these tumor viruses in OSSN suggests that they may contribute to the development of this malignancy in the HIV population. Further studies are necessary to characterize the molecular mechanisms associated with viral antigens and their potential role in the development of OSSN. URI: http://hdl.handle.net/10311/565 Files in this item: 1
Multiple oncogenic.pdf (3.107Mb) -
Gnonlonfin, G.J.B.; Hell, K.; Fandohan, P.; Siame, A.B. (Elsevier B.V. www.elsevier.com/locate/ijfoodmicro, NaN, 2008)[more][less]
Abstract: The presence of fungi, aflatoxins and fumonisin B1 in cassava and yam chips (during 28 processing and storage) were evaluated during two consecutive seasons in two agroecological zones of Benin (Northern Guinea Savannah, NGS and Sudan Savannah, SS). The Benin samples were assessed for moisture content, fungal infestation and total aflatoxin and fumonisin B1 contamination. During the two seasons, samples collected from the NGS, had moisture contents ranging from 10.0 to 14.7% in cassava chips and from 11.4 to 15.3% in yam chips. In samples from the SS, moisture content ranged from 10.1 to 14.5% and 11.1 to 14.5% in cassava and yam chips, respectively. A. flavus was the predominant fungal species. The maximum cfu/g in cassava and yam chips was 8950 and 6030, respectively. Other fungal species isolated included P. chrysogenum, M. piriformis, Phoma sorghina, F. verticillioides, R. oryzae and Nigrospora oryzae. High performance liquid chromatography analysis of both cassava and yam chips showed no contamination by either aflatoxins or fumonisin B1. URI: http://hdl.handle.net/10311/317 Files in this item: 1
Mycoflora and natural occurrence.pdf (5.959Mb) -
Cao, Y.; Allameh, S.; Sethiaraj, S. (Elsevier, NaN, 2006)[more][less]
Abstract: This paper presents the results of nanoindentation experimental studies of the contact-induced deformation in Au and Ag thin films. The paper examines the effects of film thickness and substrate deformation restraint on the mechanical properties of electron beam (e-beam) deposited Au and Ag films. Following a brief description of film microstructure, surface topography, and contact-induced pile-up deformation, film mechanical properties (hardness and Young’s modulus) were determined using nanoindentation techniques. The indentation size effects (ISE) observed in films with different thicknesses were explained using a mechanism-based strain gradient (MSG) theory. The intrinsic film yield strengths and hardnesses extracted from the MSG theory are shown to exhibit classical Hall–Petch dependence on the inverse square root of the average film grain size. Displacement bursts were also found to occur in Ag films at indentation load levels of 100 N. These were attributed to the initial onset of dislocation slip activity, when the shear stress exceeds the estimated theoretical shear strengths of the materials. URI: http://hdl.handle.net/10311/537 Files in this item: 1
Nanoindentation measurements.pdf (1.173Mb)