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Comparative study of a vitrinite-rich and an inertinite-rich Witbank coal (South Africa) using pyrolysis-gas chromatography 被引量:2
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作者 Ofentse M.Moroeng Vimbai Mhuka +2 位作者 Mathew M.Nindi RJames Roberts Nicola J.Wagner 《International Journal of Coal Science & Technology》 EI 2019年第4期621-632,共12页
This study aims to compare iso-rank vitrinite-rich and inertinite-rich coal samples to understand the impact of coal-forming processes on pyrolysis chemistry.A medium rank C bituminous coal was density-fractionated to... This study aims to compare iso-rank vitrinite-rich and inertinite-rich coal samples to understand the impact of coal-forming processes on pyrolysis chemistry.A medium rank C bituminous coal was density-fractionated to create a vitrinite-rich and an inertinite-rich sub-sample.The vitrinite-rich sample has 83 vol% total vitrinite (mineral-matter-free basis),whereas the inertinite-rich counterpart has 66 vol% total inertinite.The vitrinite-rich sample is dominated by collotelinite and collodetrinite.Fusinite,semifusinite,and inertodetrinite are the main macerals of the inertinite-rich sample.Molecular chemistry was assessed using a pyrolysis gas chromatograph (py-GC) equipped with a thermal desorption unit coupled to a time of flight mass spectrometer (MS) (py-GC/MS) and solid-state nuclear magnetic resonance (13C CP-MAS SS NMR).The pyrolysis products of the coal samples are generally similar,comprised of low and high molecular weight alkanes,alkylbenzenes,alkylphenols,and alkyl-subtituted polycyclic aromatic hydrocarbons,although the vitrinite-rich sample is chemically more diverse.The lack of diversity exhibited by the inertinite-rich sample upon pyrolysis may be interpreted to suggest that major components were heated in their geologic history.Based on the 13C CP-MAS SS NMR analysis,the inertinite-rich sample has a greater fraction of phenolics,reflected in the py-GC/MS results as substituted and unsubstituted derivatives.The greater abundance of phenolics for the inertinite-rich sample may suggest a fire-related origin for the dominant macerals of this sample.The C2-alkylbenzene isomers (p-xylene and o-xylene) were detected in the pyrolysis products for the vitrinite-rich and inertinite-rich samples,though more abundant in the former.The presence of these in both samples likely reflects common source vegetation for the dominant vitrinite and inertinite rnacerals. 展开更多
关键词 Py-TD-GC-TOFMS Main KAROO Basin Pyrolysis products 13C CP-MAS SS NMR Molecular chemistry Phenolics Xylene(C2-alkylbenzene)isomers
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Greenhouse and Field Evaluation of Selected Sweetpotato (<i>Ipomoea batatas</i>(L.) LAM) Accessions for Drought Tolerance in South Africa 被引量:2
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作者 Babajide Olusegun Omotobora Patrick Olusanmi Adebola +2 位作者 David Mxolisi Modise Sunette Marlize Laurie Abe Shegro Gerrano 《American Journal of Plant Sciences》 2014年第21期3328-3339,共12页
Sweetpotato is a major staple food in the world. It is a good source of carbohydrates, vitamin A, vitamin C and protein. The maximum production potential of the crop is being hampered by severe drought which ravages m... Sweetpotato is a major staple food in the world. It is a good source of carbohydrates, vitamin A, vitamin C and protein. The maximum production potential of the crop is being hampered by severe drought which ravages most parts of Africa. The main aim of this study therefore was to screen accessions of sweetpotato for drought tolerance in a quick screening method, followed by field screening with a view to identify accessions that can perform well under water stress conditions. Fifty sweetpotato accessions consisting of cultivars and breeding lines collected from the ARC-VOPI gene bank were planted for drought screening in the glass house for six weeks during which water was withheld to induce stress. Observations were made on number of dead plants and days to wilting point. The results were analyzed and 12 best performing accessions were selected for field trials. The field trial was carried out in Lwamondo, Limpopo province, a drought prone area in South Africa, under rain-fed conditions. The best performing accessions were Zapallo, Tacna, Ejumula, 2004-9-2 and Ndou. 展开更多
关键词 ACCESSIONS Drought SWEETPOTATO Tolerance
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Social organization of a flock of Helmeted Guineafowl(Numida meleagris)at the Krugersdorp Game Reserve,South Africa 被引量:2
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作者 J.H.VAN NIEKERK 《Chinese Birds》 2010年第1期22-29,共8页
The social organization of marked Helmeted Guineafowl(Numida meleagris) was studied in the Krugersdorp Game Reserve(Gauteng Province,South Africa) during March 1982 to February 1984.Flock members(7-10 guineafowl) did ... The social organization of marked Helmeted Guineafowl(Numida meleagris) was studied in the Krugersdorp Game Reserve(Gauteng Province,South Africa) during March 1982 to February 1984.Flock members(7-10 guineafowl) did not associate randomly.Helmeted Guineafowl must live in a sociable flock to survive in the wild.The highest ranking male(male A) formed the pivot of the daily activities of the flock,such as determining foraging direction.High ranking males(males A and B) associated closely to repulse conspecific intruders.Breeding females associated more often with the high ranking males during the breeding season.Although a pecking order was established among males,the frequency of agonistic actions within the flock was very low,which suggests that agonistic interactions are limited to maintain cohesion.Adult females remained between the dominant male and the juveniles to minimize victimization.The second highest ranking male(B) took center stage while the dominant male and his female left temporarily to breed and then the rest of the flock clustered around him to maintain the cohesive nature of the flock.Most adults assisted with the brooding of the chicks of the highest ranking male.Flocking is,among other functions,a predator surveillance strategy that enables the Helmeted Guineafowl to forage under conditions with very limited ground cover and to maximize food finding during winter. 展开更多
关键词 Numida meleagris social organization DOMINANCE COOPERATION
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Groundwater Modelling of Motloutse Alluvial Aquifer, Eastern Botswana
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作者 Edwin O. Keaitse Nata T. Tafesse +2 位作者 Berhanu F. Alemaw Kebabonye Laletsang Read B. M. Mapeo 《Journal of Water Resource and Protection》 CAS 2024年第10期627-639,共13页
The potential groundwater reserve in alluvial aquifers and sandy river beds has not been well studied, and yet their benefit in meeting rural water supply demands cannot be underestimated. A three-dimensional steady-s... The potential groundwater reserve in alluvial aquifers and sandy river beds has not been well studied, and yet their benefit in meeting rural water supply demands cannot be underestimated. A three-dimensional steady-state finite difference numerical groundwater flow model was used to assess the groundwater resource potential on a one-kilometre river stretch scale along the Motloutse River catchment in eastern Botswana. The model area is a single-layer unconfined aquifer system. A uniform grid was laid over this phreatic aquifer, and an overall size of 50 columns x 54 rows was developed. The model yielded calibrated K values of 145 m/day and 11 m/day for the riverbed and riverbank sediments, respectively, and calibrated recharge and evaporation of 172 mm/yr and 120 mm/yr, respectively. A sustainable groundwater yield of 120 m3/day with the potential to irrigate an area of 2.4 hectares was determined. The result also shows that the Motloutse alluvial aquifer yields a safe yield of 29,400 m3 for a kilometre of river stretch. 展开更多
关键词 Alluvial Aquifer GROUNDWATER Hydraulic Conductivity Motloutse River Eastern Botswana
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Determination and Quantification of Proximate and Mineral Composition for 20 Improved Sorghum Varieties Grown in Machache, Lesotho
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作者 Malefane Ts’ephe Puleng Letuma +4 位作者 Karabelo Khomongata Fisseha Itanna Mamoipone Sebitia Monica Lephole Pitso Masupha 《Food and Nutrition Sciences》 CAS 2024年第8期744-758,共15页
Twenty varieties of improved sorghum were grown in Machache at the Department of Agricultural Research station, located (29˚22'60"S and 27˚52'0"E) in the central foothills of Lesotho in Maseru distri... Twenty varieties of improved sorghum were grown in Machache at the Department of Agricultural Research station, located (29˚22'60"S and 27˚52'0"E) in the central foothills of Lesotho in Maseru district. The varieties were planted in a randomized complete block design. At maturity, they were harvested, dried, threshed, milled and analyzed in the crop science laboratory at the National University of Lesotho. The proximate and mineral contents were analyzed from samples in a completely randomized design with three replicates. The proximate composition parameters measured were crude proteins, crude fiber, crude fat, moisture content, and carbohydrates. The minerals analyzed were, phosphorus, sodium, calcium, magnesium, potassium, copper, zinc, iron, and magnesium. The results showed the nutritional contents ranging from (4.7% - 16.16%), (0.35% - 2.10%), (1.25% - 4.00%), (71.60% - 84.06%), (5.53% - 10.18%), for protein, fat, fiber and carbohydrate, and moisture content, respectively. Mineral content ranged from (1342.96 - 3500.34 mg/kg), (25.97 - 185.25 mg/kg), (50.71 - 511.71 mg/kg), (29.35 - 4542.13 mg/kg), (577.19 - 3041.52 mg/kg), (0.25 - 4.07 mg/kg), (1.96 - 18.61 mg/kg), (67.14 - 122.96 mg/kg), (4.73 - 11.39 mg/kg) for phosphorus, sodium, calcium, magnesium, potassium, copper, zinc, iron, and manganese respectively. The following varieties were found to have the highest and appreciable amounts of nutrients and minerals that are crucial in the country diet;protein content was KARI Mtama 1, zinc, IESX 16 2533-SB-SSI-19, and iron IESX 16 2535-SB-SSI-34. 展开更多
关键词 VARIETIES SORGHUM PROXIMATE MINERAL
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Household Solid Waste Awareness and Practices among Residents of Windhoek, Namibia
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作者 Jolosi Mukena Youcai Zhao Songa Mutonga 《Journal of Environmental Protection》 2024年第6期641-655,共15页
This study explores household solid waste management (HSWM) practices and awareness among residents of Windhoek West, a rapidly urbanizing constituency in the Khomas Region of Namibia. Employing a descriptive methodol... This study explores household solid waste management (HSWM) practices and awareness among residents of Windhoek West, a rapidly urbanizing constituency in the Khomas Region of Namibia. Employing a descriptive methodology, the research investigates the interplay between public awareness, regulatory frameworks, and the availability of waste management facilities to assess their impact on waste management behaviors. Our findings indicate significant gaps in both knowledge and infrastructure that hinder effective waste management. The study reveals that while there is a high willingness among residents to engage in recycling and waste reduction, actual practices are limited due to inadequate facilities and lack of stringent enforcement of waste policies. This research identifies key factors that influence waste management practices, including demographic characteristics and access to waste management facilities. It also proposes actionable strategies such as expanding recycling and sorting facilities, enhancing educational campaigns tailored to local needs, and implementing regular enforcement mechanisms. These strategies are aimed at improving compliance with waste management protocols and fostering a culture of environmental responsibility. The results of this investigation show the critical role of ongoing education and infrastructural improvement in bridging existing knowledge gaps and facilitating effective waste management practices. This research lays a foundational step toward enhancing sustainable urban development and effective waste management in Windhoek, providing valuable insights for policymakers, community leaders, and stakeholders engaged in urban environmental management. 展开更多
关键词 Household Solid Waste Management (HSWM) Public Awareness Waste Segregation Windhoek West Recycling Facilities
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The Key Triggers for the Transitioning of Informal SMMEs to Formal SMMEs:A Baseline Survey of the Gauteng Province——South Africa
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作者 Paul Kibuuka Deon Tustin 《Psychology Research》 2019年第1期32-44,共13页
This paper presents the views of 623 informal and formal small,medium,and micro enterprises(SMMEs)operating in the Gauteng Province of South Africa.The objective of the study was to identify challenges and benefits th... This paper presents the views of 623 informal and formal small,medium,and micro enterprises(SMMEs)operating in the Gauteng Province of South Africa.The objective of the study was to identify challenges and benefits that are experienced by SMMEs during and after the registration process leading to the transition from informal to formal business,the level of awareness by the SMMEs of the registration information,and the procedures in addition to the potential factors that inspire or discourage informal and prospective business registration.The reason for including both informal and formal SMMEs in the survey was to compare the perceptions of these groups of businesses regarding the triggers and/or barriers to register as a formal business.The results show that for both informal and formal businesses,the liability of paying taxes was a major challenge while improved workers’health and safety accrued as a major benefit.Own research emerged as the main source of access to business registration information and procedure.The costs involved in registration were highlighted as one of the major factors discouraging registration but the prospects of expanding the customer base and the ability to achieve a higher turnover as some of the main inspiring factors.The study recommends the development of policies that provide an enabling environment for sustainable enterprises but also to implement measures that improve productivity through access to finance,skills,infrastructure,markets,and technology transfers. 展开更多
关键词 SMME INFORMAL TRIGGERS business registration transition FORMAL EMPLOYEES TURNOVER and South AFRICA
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Vocal behavior of Crested Guineafowl(Guttera edouardi) based on visual and sound playback surveys in the Umhlanga Lagoon Nature Reserve,Kwa Zulu-Natal province,South Africa
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作者 Johann H.van Niekerk 《Chinese Birds》 CSCD 2015年第3期132-139,共8页
Background:Generally speaking,playbacks were often ineffective to determine the group sizes of birds since mainly males from leks responded.This limitation has not been tested properly for flocking birds such as Crest... Background:Generally speaking,playbacks were often ineffective to determine the group sizes of birds since mainly males from leks responded.This limitation has not been tested properly for flocking birds such as Crested Guineafowl(Guttera edouardi) with the view to use it as a counting method.The aims of the study reported in this paper were(1) to describe the cal s of Crested Guineafowl in a social context;(2) to interpret cal s in an evolutionary context;and(3) to demonstrate that playbacks can be used to locate and count Crested Guineafowl in smal isolated forests.Methods:The vocal behavior of Crested Guineafowl was observed during a survey conducted in the Umhlanga Lagoon Nature Reserve(Kwa Zulu-Natal,South Africa) from November 2010 to June 2012.Transect line observations and sound playback methods were used.Results:The behavioral context and structure of cal s were described.The eight cal s described for Crested Guineafowl were produced mainly to unite flock members in the dense understory,where visibility was poor,and to repel intruders.When not disturbed,Crested Guineafowl were quiet and only made soft contact calls.Conclusions:The high rate of call back and the fact that flocks invariably approach the source of the call en masse,shows that field researchers are able to assess the population size of Crested Guineafowl with sound playbacks along a transect.The value of playbacks as a conservation tool is assessed. 展开更多
关键词 Guttera edouardi PLAYBACK CALLS Social behavior FLOCKING TRANSECT surveys
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Population structure and mating system of the Red-crested Korhaan(Lophotis ruficrista) in South Africa
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作者 Johann H van Niekerk 《Chinese Birds》 CSCD 2015年第1期43-51,共9页
Background: The mating system of the korhaans and bustards in southern Africa is either based on polygyny or monogamy. The Red-crested Korhaan(Lophotis ruficrista) has been described as polygynous but otherwise very l... Background: The mating system of the korhaans and bustards in southern Africa is either based on polygyny or monogamy. The Red-crested Korhaan(Lophotis ruficrista) has been described as polygynous but otherwise very little is known about its breeding biology. The aims were to describe the population structure and male behavior during breeding.Methods: The data collected for this paper was mainly based on field transect surveys carried out in 2009, 2010 and 2011. The population structure of the Red-crested Korhaan in the temperate Borakalalo Game Reserve(BGR)was compared with that in the arid Molopo Nature Reserve(MNR)(both situated in the North West province of South Africa). The study was mainly conducted in the BGR but additional work was conducted in the MNR for comparison.Results: The difference in mean group sizes between MNR(1.03) and BGR(1.07) was statistically not significant.Group sizes were not affected by climate despite the fact that the BGR received about 650 mm precipitation per annum and the MNR about 200 mm. In both reserves the apparent sex ratios were skewed in favor of males(1:0.29 in the BGR and 1:0.1 in the MNR). The population was dispersed in a clumped manner which is ascribed to the formation of leks. Leks were positioned in open habitat while females invariably concealed themselves under cover.Conclusions: The leks formed the pivot of the mating system of the Red-crested Korhaan and are identifiable social structures that field ecologists can use to monitor population stability. 展开更多
关键词 Lophotis ruficrista LEKS MATING system DISPERSION GROUP SIZE
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Mental Health Impacts of Information and Communication Technology Usage in South Africa
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作者 Akinboade Oludele Akinloye Obareng Baldwin Manoko +1 位作者 Mmafani Serote Trevor Taft 《International Journal of Mental Health Promotion》 2021年第2期255-276,共22页
This study examined mental health issues affecting the group of individuals who are in the social media contact list of the researchers.This was done by administering a closed structured questionnaire,covering informa... This study examined mental health issues affecting the group of individuals who are in the social media contact list of the researchers.This was done by administering a closed structured questionnaire,covering information from participants’demographic characteristics,duration of time spent on ICT usage,to their perceived health effects thereof.Male respondents,largely unemployed are active ICT users,addicted to the Internet,and also suf-fer from unspecified ailments.Aged 31–35 and above,half of men and all women participants spend more than 5 h per day.High-intensive ICT use is associated,in general,with concurrent symptoms of information overload,depression and Internet addiction.It is insignificantly associated with composite stress.Medium intensive ICT use is correlated with fatigue and depression in equal measure but in opposite direction.There are significant differ-ences in demographic attributes as they explain intensity of ICT Usage.The older the employed survey partici-pants are,the less they suffer from composite stress.However,black South Africans suffer significantly from composite stress,fatigue and depression,though negatively from internet addiction.The results also indicate that South African men have negative experiences of composite stress,depression and internet addiction.Educated South Africans have negative experiences of fatigue,but positive experiences of composite stress,depression and internet addiction.Low intensive use of ICT has no impact on composite stress,fatigue and depressive moods of survey participants.It impacts negatively on internet addiction.Medium intensive use of ICT impacts posi-tively on survey participants’experiences of fatigue,but negatively on composite stress,depression and internet addiction.High-intensive use of ICT impacts positively on survey participants’experiences of composite stress and depression. 展开更多
关键词 Information and communication technology mental health Internet addiction DEPRESSION FATIGUE
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Facilitative Institutional Infrastructure to Optimise Productive Participation of Rural People in Local Development Processes: South Africa
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作者 Lennox Mzuhleli Garane Paul Kibuuka 《Psychology Research》 2019年第7期284-302,共19页
Pervasive low levels of education and weak civil society activism in poor rural communities are cited as constraining factors for participatory development (PD), resulting in technical capacity for participation being... Pervasive low levels of education and weak civil society activism in poor rural communities are cited as constraining factors for participatory development (PD), resulting in technical capacity for participation being skewed against the community participants. This paper highlights the outcomes of a research study that examined the applicability of the participatory development concept in conditions characterised by low levels of education and weak civil society. The research was undertaken in two rural villages in the Eastern Cape Province of South Africa, utilising both quantitative and qualitative approaches entailing interviews with 18 key informants followed by two focus group discussions each with seven participants respectively. The research found that rural communities were not aware of the government policy placing people participation at the centre of rural development interventions;and that they would not support it as they believed it was government's role to champion their development. The research also found that the government officials that lead the implementation effort of the rural development programmes did not believe that the participation policy was practical, citing capacity limitations among rural communities. The researcher recommends a moderated rural people participation process, which features creation of a facilitative institutional infrastructure to optimise productive participation of rural people in local development processes. 展开更多
关键词 PARTICIPATORY development people PARTICIPATION RURAL COMMUNITIES INSTITUTIONAL INFRASTRUCTURE
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The Determinants of Risk Exposure When Development Finance Institutions Consider Approval of Funding to Different Development Markets—Case Study Development Bank of Southern Africa
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作者 Paul Kibuuka Njabulo Shandu 《Psychology Research》 2020年第9期359-381,共23页
This paper evaluates the determinants of risk exposure when development finance institutions consider approval of funding to different development markets utilising multiple regression econometric models and the Devel... This paper evaluates the determinants of risk exposure when development finance institutions consider approval of funding to different development markets utilising multiple regression econometric models and the Development Bank of South Africa(DBSA)as a case study.The research presents the classical development finance institution(DFI)business model and market size estimation with the contemporary DFI risk classification and enterprise risk management framework.In addition to reviewing the profile of financial and non-financial products and services,the related project cycles and the DFI credit risk pricing and mitigation approaches for the different development markets.Our results suggest that there is a correlation between the funding of under-resourced municipalities by DBSA and its exposure to financial risk though the correlation is not overwhelmingly significant,but also evidence of a negative correlation between the funding of under-resourced municipalities and the minimization of the financial risk exposure of DBSA.Likewise,there is a negative correlation between funding to all three different sizes of a municipality and ability of the DFI to absorb future losses(non-performing loan coverage ratio).The negative correlation is highest for secondary cities followed by metros and least for under resourced municipalities.The research concludes with four major recommendations of what the role of the DFI should be in enhancing access of under-resourced municipalities to development funding. 展开更多
关键词 development finance institution(DFI) risk exposures development markets multiple regression and South Africa
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Implementing the Curriculum and Assessment Policy Statement: A Case Study of the Vhembe West District, South Africa
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作者 Rammbuda Mulatedzi Calvin 《Journal of International Education and Practice》 2019年第2期45-57,共13页
This qualitative study was undertaken to investigate how district officials implemented Curriculum and Assessment Policy Statement in the Vhembe West District in South Africa.Interview data were collected and used for... This qualitative study was undertaken to investigate how district officials implemented Curriculum and Assessment Policy Statement in the Vhembe West District in South Africa.Interview data were collected and used for themes identification.The study identified the following challenges that the district officials experienced as they performed their duties:insufficient resources,lack of finances to buy learning and teaching support materials,infrastructure failures,the district’s inadequate support to schools,shortage of district officials in certain disciplines,unclear roles,lack of collaboration,unavailability of followup visits,the shortage of computers for the district officials and teacher support materials,bribery and corruption of selling principalship posts,slow filling of district officials posts,and inappropriate skills for school management and leadership.The study concluded that qualified district officials should be appointed,ongoing support from the Department of Basic Education and provision of resources in ensuring smooth curriculum implementation is needed,and bribery and corruption should be stopped when school principal appointments are made.This study also concludes that the district officials should be continuously capacitated so that they should be able to meet curriculum challenges,and the Department of Basic Education should speed up the curriculum delivery by ensuring that the vacancies are filled up. 展开更多
关键词 Challenges CURRICULUM Curriculum Change Curriculum Implementation Curriculum and Assessment Policy Statement District Officials Empowering Management Stakeholders Vhembe West District
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A Number Theoretic Analysis of the Enthalpy, Enthalpy Energy Density, Thermodynamic Volume, and the Equation of State of a Modified White Hole, and the Implications to the Quantum Vacuum Spacetime, Matter Creation and the Planck Frequency
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作者 Michele Nardelli Amos S. Kubeka Alizera Amani 《Journal of Modern Physics》 2024年第1期1-50,共50页
In this paper, we analyze the enthalpy, enthalpy energy density, thermodynamic volume, and the equation of state of a modified white hole. We obtain new possible mathematical connections with some sectors of Number Th... In this paper, we analyze the enthalpy, enthalpy energy density, thermodynamic volume, and the equation of state of a modified white hole. We obtain new possible mathematical connections with some sectors of Number Theory, Ramanujan Recurring Numbers, DN Constant and String Theory, that enable us to extract the quantum geometrical properties of these thermodynamic equations and the implication to the quantum vacuum spacetime geometry of our early universe as they act as the constraints to the nature of quantum gravity of the universe. 展开更多
关键词 Number Theory Ramanujan Recurring Numbers DN Constant String Theory Loop Quantum Gravity Matter Creation Enthalpy Energy Density Thermodynamic Volume ENTHALPY
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Collaborative Research between South Africa and China:An Overview of Literacy Development in Grade R Classes in South Africa
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作者 Norma Margaret Nel 《浙江外国语学院学报》 2016年第6期85-94,共10页
The main aim is to give a synopsis of the articles which were the first of three phases of an international collaborative research project betweAfrica and a university in China.The overall theme of the project was:Lit... The main aim is to give a synopsis of the articles which were the first of three phases of an international collaborative research project betweAfrica and a university in China.The overall theme of the project was:Literacy development in mary schools.Firstly,an introduction,including the benefits and challenges of the intesearch project collaboration based on reports in literature,is discussed.Secondly,the background othe South Africa-China project and its three phases is described.Thirdly,the literacy developmin primary schools in South Africa is discussed.Lastly,a synopsis of the South African tea’s em-pirical findings providing overviews of literacy development within the early ban and rural education in South Africa is presented.These overviews(together with two remaioverviews not included in this article)serve as a point of departure for the second phasearch project. 展开更多
关键词 英语学习 学习方法 阅读知识 阅读材料
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On the Edge of Malfeasance: Informal African Immigrant Traders in the/ohannesburg Inner City, South Africa
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作者 Inocent Moyo Trynos Gumbob 《Sociology Study》 2014年第4期323-333,共11页
Admittedly, the stratospheric rise of Informal African Immigrant Traders (IAIT) in the Johannesburg inner city within a climate of discrimination, harassment, hostility, and xenophobia has engendered survival strate... Admittedly, the stratospheric rise of Informal African Immigrant Traders (IAIT) in the Johannesburg inner city within a climate of discrimination, harassment, hostility, and xenophobia has engendered survival strategies which border on the illegal and underground. Based on an in-depth interview study of 40 IAIT, operating in the Johannesburg inner city and specialising in clothes, cellphone and accessories, household goods, fruits and vegetables, and a courier company, this paper posits that the registered and unregistered IAIT operate side by side with the latter operating from undesignated sites, either bribing or deceitful evading the Johannesburg Metropolitan Police (JMP). Is this the characteristic of IAIT in the Johannesburg inner city? Ostensibly, the success of challenging the institutional regulatory regime points to the possibility of African immigrant traders existing on the edge of impropriety or lawlessness. To this end, there is a need for comprehensive policy initiatives starting from the national and cascading to the provincial and municipality levels that will effectively address and manage urban informality, including the activities of the IAIT, failing which these will fuel operations outside the regulatory regimes and the mushrooming of the underground economic activities. 展开更多
关键词 African immigrant traders urban informality discrimination JOHANNESBURG South Africa
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Observations of Red-billed Spurfowl(Pternistis adspersus) in the arid Molopo Nature Reserve,North West Province,South Africa
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作者 Johann H.VAN NIEKERK 《Chinese Birds》 2011年第3期117-124,共8页
Field work was conducted in the southern half of the Molopo Nature Reserve(MNR) near Vostershoop in the North West Province of South Africa to(1) describe the past and present distribution of Red-billed Spurfowl(Ptern... Field work was conducted in the southern half of the Molopo Nature Reserve(MNR) near Vostershoop in the North West Province of South Africa to(1) describe the past and present distribution of Red-billed Spurfowl(Pternistis adspersus) in South Africa and(2) to describe the dispersion of Red-billed Spurfowl at waterholes in the MNR.The Red-billed Spurfowl did not colonize this area from Bo-tswana in the 1990s as reported in Hockey et al.(2005) and their distribution status and population sizes are not determined by long distance(30-100 km) and/or seasonal movements between the two countries.Red-billed Spurfowl are sparsely distributed and mainly occur in clusters near man-made waterholes.Waterholes provide water and food found in and around antelope droppings.The movement of the Red-billed Spurfowl between waterholes over short distances of 2-5 km was probably encouraged by the sinking of more boreholes since the 1980s(and the creation of 'veeposte'(game/livestock camps) around them).Low rainfall that results in limited insects is probably the single most important factor limiting populations of the Red-billed Spurfowl in South Africa. 展开更多
关键词 Pternistis adspersus dispersion waterholes arid environment group sizes
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Observations on movements of Double-banded Sandgrouse (Pterocles bicinctus) in Borakalalo National Park, North West province, South Africa
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作者 Johann H. VAN NIEKERK 《Chinese Birds》 2012年第1期47-53,共7页
The main purpose of this study was to describe the intrinsic (breeding) and extrinsic factors (rainfall/vegetation) that might trigger movements of Double-banded Sandgrouse (Pterocles bicinctus) in Borakalalo National... The main purpose of this study was to describe the intrinsic (breeding) and extrinsic factors (rainfall/vegetation) that might trigger movements of Double-banded Sandgrouse (Pterocles bicinctus) in Borakalalo National Park, South Africa. The park is situated 80 km north of Pretoria and 30 km north of Jericho in the North West province. Data collection was based on traversing the reserve for two days per month along a set route (32 km) with a vehicle at 10 km·h 1 during 2010. The mean group size of this Double-banded Sandgrouse was 2.47. The male to female ratio in the population was 1:0.87. They were often observed in the road, on short trampled grass or in burnt thornvelds with green sprouts. Double-banded Sandgrouse were mainly present in the reserve during two relatively dry periods, from February––MMMaaarrrccchhh and again from July––SSSeeepppttteeemmmbbbeeerrr 2010. They wwwwweeeeerrrrreeeee more regularly observed in the hinterland of the park in the mornings and conversely, during the late afternoons they were more regularly observed closer to the edge of the Klipvoor Dam. Five possible reasons are discussed that may affect the movement of the Double-banded Sandgrouse: annual rainfall, short spells of high/low rainfall periods within the rainy season, daily flights of 2–4 km to drink water, breeding and veld conditions. 展开更多
关键词 Double-banded Sandgrouse BREEDING RAINFALL vegetation
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Ticks, Demographics, Vegetation Cover, and Farmer’s Age Influence Red Meat Production in Resource-Poor Regions of Eastern Cape Province of South Africa
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作者 Nkululeko Nyangiwe Sindisile Goni +13 位作者 Thami Khethani Tanki Thubela Mlungisi Jansen Siza Mthi Mandla Yawa Sive Tokozwayo Unathi Gulwa Ntanganedzeni O. Mapholi Ishmael F. Jaja Luxolo Qokweni Yanga Mkabile Mkabile Sindile Magoda Zoleka Ntondini Zamantungwa T. H. Khumalo 《Open Journal of Animal Sciences》 2021年第4期682-696,共15页
<span style="font-family:Verdana;">This study presents an integrated examination of livestock production constraints associating with communal farming in six district municipalities (DMs) of the Easter... <span style="font-family:Verdana;">This study presents an integrated examination of livestock production constraints associating with communal farming in six district municipalities (DMs) of the Eastern Cape Province. We collected data on demographic and socio-economic factors from 271 farmers randomly given questionnaires. About 26 Land Redistribution for Agricultural Development (LRAD) owned by communal farmers were surveyed to ascertain the condition of grazing land, meanwhile, tick species and distribution on cattle and goats found in 158 sampling sites of the study area were also recorded. From the results, a total of 34,929 adult ticks belonging to five genera and 10 species were encountered. The most abundant tick genera were </span><i><i><span style="font-family:Verdana;">Rhipicephalus</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> of the subgenus <i></i></span><i><i><span style="font-family:Verdana;">Boophilus</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> (68.91%), <i></i></span><i><i><span style="font-family:Verdana;">Amblyomma</span></i><span style="font-family:Verdana;"></span></i> <span style="font-family:Verdana;">(20.72%), <i></i></span><i><i><span style="font-family:Verdana;">Hyalomma</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> (8.64%), <i></i></span><i><i><span style="font-family:Verdana;">Ixodes</span></i><span style="font-family:Verdana;"></span></i> <span style="font-family:Verdana;">(1.22%), and <i></i></span><i><i><span style="font-family:Verdana;">Haemaphysalis</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> (0.51%). By geographic distributions, <i></i></span><i><i><span style="font-family:Verdana;">Amblyomma</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> and <i></i></span><i><i><span style="font-family:Verdana;">Rhipicephalus</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> were common to all DMs, while <i></i></span><i><i><span style="font-family:Verdana;">R</span></i><span style="font-family:Verdana;">.</span> <i><span style="font-family:Verdana;">microplus</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> and <i></i></span><i><i><span style="font-family:Verdana;">R</span></i><span style="font-family:Verdana;">.</span> <i><span style="font-family:Verdana;">decoloratus</span></i><span style="font-family:Verdana;"></span></i> <span style="font-family:Verdana;">were found in the drier regions</span><span style="font-family:Verdana;">. </span><span style="font-family:Verdana;">From the map plotted for 16 custom feeding centers, lack of marketing channels (23%), poor animal conditions (20%), lack of infrastructure (19%), high price of medicine (14%), shortage of feed (10%), stock theft (8%), and age of animals (too old) to be marketed (6%) are the major shortcomings in red meat production. We found that the associations between gender (</span><i><span style="font-family:Verdana;">χ</span></i><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 31.3481, <i></i></span><i><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> < 0.0001), age (</span><i><span style="font-family:Verdana;">χ</span></i><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 32.4889, <i></i></span><i><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> < 0.0001), and farming experience (</span><i><span style="font-family:Verdana;">χ</span></i><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 52.7556, <i></i></span><i><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> < 0.0001) were significantly (<i></i></span><i><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> < 0.05) higher. Additionally, we found that farming commodities were significantly influenced by gender and farming experience. From the surveyed LRAD farms, we observed a higher proportion of increaser II grass species in Alfred Nzo (55.6%), Amathole (53.9%), and Chris Hani (46.4%) DMs. On the other hand, the decreaser grass species were few in Alfred Nzo (16.5%), Amathole (13.8%), and Chris Hani (21.8%). Inferences from the data indicate the need for government and stakeholders’ intervention to farmers through the provision of infrastructures, marketing channels, and training on livestock based programs.</span> 展开更多
关键词 Amblyomma Constraints Rangeland Conditions Rhipicephalus (Boophilus) microplus Tick Distribution South Africa
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Productivity Evaluation of Four Medicago sativa Cultivars under Two Water Regimes (Irrigated and Non-Irrigated) and Two Soil Types at Bathurst Research Station in the Eastern Cape Province, South Africa
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作者 Mhlangabezi Solontsi Mfundo Phakama Maqubela +5 位作者 Johan Adam van Niekerk Jan Willem Swanepoel Gideon Jordaan Unathi Gulwa Sive Tokozwayo Nkululeko Nyangiwe 《Agricultural Sciences》 2022年第3期438-447,共10页
Medicago sativa (lucerne) is a perennial and drought tolerant fodder crop which is widely used as feed for livestock in South Africa. This study evaluated four lucerne cultivars under two water regimes and also determ... Medicago sativa (lucerne) is a perennial and drought tolerant fodder crop which is widely used as feed for livestock in South Africa. This study evaluated four lucerne cultivars under two water regimes and also determined the effect of soil type on lucerne biomass production. To determine dry matter production per cultivar per treatment, a random grid (quadrant) sampling method was used and all biomass within that radius was cut to 5 cm above the ground level in each plot. All biomass sampling was done just before regrowth commences. Biomass data collection on four lucerne cultivars belonging to different dormancy groupings (WL 711, WL 525 HQ, KKS 9911 and SA Standard) were collected seasonally under different soil types on both irrigated and non-irrigated plots and analysed. Soil type (site) had a significant (P < 0.05) effect on the overall quantity of dry matter produced as more dry matter was produced in site 2 (S2) in comparison to site 1 (S2). Different levels of water application (moisture supplementation) also affected the quantity of dry matter produced in each soil type. The once-a-month irrigation treatment (Ir1) led to the production of superior dry matter yield on SI even though the effect was not significant. In S2 twice a month irrigation treatment (Ir2) produced the highest dry matter, however, this effect was significant (P < 0.05) only in comparison with zero irrigation (Ir0) treatment. Cultivar 3 (KKS 9911) was the least productive cultivar in S1, while the same cultivar was the least productive cultivar in S2. These findings show that both soil type and irrigation levels had a significant (P < 0.05) effect on the total dry matter production of the tested Lucerne cultivars belonging to different dormancy groupings. 展开更多
关键词 Biomass CULTIVAR Dry Matter Dormancy Groupings
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