97 research outputs found
Copper’s Corollaries: Trade and Labour Migration in the Copperbelt (1910-1940)
The geopolitical importance of the mining industry in Zambia and Katanga, and the rural-urban migration patterns that it brought about, has been the subject of many studies. And yet, the extent to which these industries were interdependent is often downplayed or overlooked. Looking more closely at the history of the Zambian and Katangese Copperbelts, one can see that, despite their separateness, there was interplay between them. During the British South Africa Company rule of Rhodesia (1899-1924), Northern Rhodesia was developed as an important labour and food reserve for the Katangese mines. Following the onset of the Great Depression in the early 1930s, Katanga’s dependence on Northern Rhodesia diminished as the Katangese mines found new sources of labour and foodstuffs. Yet, at the same time, it appears that the Depression served to make the border more porous than it had been before. People of all origins crisscrossed the border between Belgian and British Africa to look for employment or to sell their produce. This article aims to bring this interaction to light
Copper’s Corollaries: Trade and Labour Migration in the Copperbelt (1910-1940)
The geopolitical importance of the mining industry in Zambia and Katanga, and the rural-urban migration patterns that it brought about, has been the subject of many studies. And yet, the extent to which these industries were interdependent is often downplayed or overlooked. Looking more closely at the history of the Zambian and Katangese Copperbelts, one can see that, despite their separateness, there was interplay between them. During the British South Africa Company rule of Rhodesia (1899-1924), Northern Rhodesia was developed as an important labour and food reserve for the Katangese mines. Following the onset of the Great Depression in the early 1930s, Katanga’s dependence on Northern Rhodesia diminished as the Katangese mines found new sources of labour and foodstuffs. Yet, at the same time, it appears that the Depression served to make the border more porous than it had been before. People of all origins crisscrossed the border between Belgian and British Africa to look for employment or to sell their produce. This article aims to bring this interaction to light
Promoting and sustaining Lesson Study as a form of effective professional learning:an investigation of the practices enacted by teacher, school and system leaders
Structural characterisation of nickel-cobalt spinel-related oxides of NixCO3-xO4 (0≤x≤1.2) prepared by four different routes using XRD, FTIR, UV-VIS-NIR and XPS
AbstractFour analytical techniques, i.e. X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), ultraviolet-visible-near infrared reflectance spectroscopy (UV-vis-NIR), X-ray photoelectron spectroscopy (XPS) and four different synthesis methods, i.e the sol gel routes pechini and propionic acid route, thermal decomposition of nitrates and coprecipitation of hydoxides, have been used to characterise Ni – Co mixed oxides NixCo3-xO4 (0 ≤ x ≤ 1.2). XRD patterns show that the oxides crystallise in cubic spinel phases with a unit lattice parameter, which increases with x and closely linked to the preparation method. The UV-vis-NIR reflectance patterns confirm the two mixed valence ionic distribution. IR spectra exhibit strong peak characteristics of pure spinel. XPS study shows that there are possibly structural differences as ions site occupation or types of spinel form in compounds prepared by different methods
"Copper, borders and nation-building": the Katangese factor in Zambian political and economic history
ASC – Publicaties niet-programma gebonde
Nodulation and nitrogen fixation of field grown common bean (Phaseolus vulgaris) as influenced by fungicide seed treatment
A field experiment was conducted at Bel Air station, in Dakar using 15N isotope dilution technique and the non nodulating soybean (Glycine max) variety m129 as reference plant to test the compatibility of Dichlorofenthion-thiram (DCT) fungicide to the inoculation of common bean (Phaseolus vulgaris) Paulista variety with both Rhizobium etli ISRA 353 and R. tropici strain ISRA 554. Nodulation was not induced with R. etli ISRA 353 and nitrogen fixation did not occur. With R. tropici ISRA 554, a decrease in nodulation was observed, but nitrogen fixation was not significantly different compared to that of the non DCT-treated common bean.
(African Journal of Biotechnology: 2003 2(7): 198-201
SYNTHESIS AND CHARACTERIZATION OF Ni0.4Co2.6O4 SPINEL MIXED OXIDES POWDER: STUDY OF ITS SURFACE PROPERTIES BY VOLTAMMETRY, X-RAY, FTIR, UV-VIS-NIR SPECTROSCOPY AND SCANNING ELECTRON MICROSCOPY
Electrochemical studies were carried out on Ni0.4Co2.6O4 powders prepared by sol-gel via propionic acid method using cyclic and steady state voltammetries. The oxide surface was characterized by scanning electron microscopy (SEM), X-ray diffraction, UV-vis-NIR and FTIR spectroscopies. The results showed that the formation of homogeneous oxide with a single spinel phase occurred at 350°C. The surface redox couple NiOOH/Ni(OH)2 is confined on the surface material l.
KEY WORDS: Ni0.4Co2.6O4 spinel mixed oxides powder, Sol-gel process, Surface properties
Bull. Chem. Soc. Ethiop. 2005, 19(2), 213-220
Factores que influyen en la elección de una opción ocupacional en los estudiantes de CETPRO 2014
La investigación titulada factores que influyen en la elección de una opción
ocupacional en los estudiantes de CETPRO 2014, tuvo como objetivo
establecer los factores internos y externos que influyen en los estudiantes del
CETPRO PROMAE Breña 2014 para la elección de una opción ocupacional.
Este trabajo expone el desarrollo de una investigación básica sustantiva,
de nivel exploratorio, de diseño no experimental transversal descriptivo llevado
a cabo en el año 2014 en el CETPRO PROMAE Breña, con una muestra
censal de 316 estudiantes matriculados. Se aplicó un cuestionario validado por
criterio de jueces en investigación educativa, la información fue procesada a
través del software SPSS 20 y Excel 2010, se aplicó el análisis factorial para
establecer los factores que influyen en la elección de una opción ocupacional.
Se determinó que los factores que influyen en los estudiantes la elección
de una opción ocupacional en el CETPRO PROMAE Breña son internos y
externos; los internos están conformados por la motivación, vocación,
resiliencia, emprendimiento y los factores externos son lo social, económico,
educativo y laboral. Asimismo, se establece que los factores internos son los
que más influyeron en los estudiantes encuestados. Además se concluye que
el factor interno más influyente es la vocación y el factor externo más influyente
es el social
Diplomatic translation at embassies in Pretoria
The role played by translation across the globe has been well established. Translation is very important to build bridges between people who do not share the same language, especially in international organisations. This descriptive research explores the need for translation at diplomatic missions such as embassies and high commissions in Pretoria. More specifically, this study describes the way in which translation is dealt with at embassies in Pretoria, the cl ients of diplomatic translation, the different categories of documents translated and the diplomatic missions' general translation needs. In order to reach these objectives, this study uses both primary and secondary data analysis. A critical analysis of a questionnaire completed by representatives of embassies and high commissions shows that there is a real need for translation at embassies in Pretoria, especially with regards to the services provided by sworn translators.Mini Dissertation (MA)--University of Pretoria, 2018.African LanguagesMAUnrestricte
PREPARATION OF NICKEL - COBALT SPINEL OXIDES NixCO3-xO4.COMPARISON OF TWO PHYSICAL PROPERTIES STEMMING FROM FOUR DIFFERENT PREPARATION METHODS AND USING CARBON PASTE ELECTRODE
A comparative study of two electro-physical properties (porosity and electrical conductivity) of binary nickel cobalt oxides electrodes with spinels mixed oxides NixCo3-xO4 as active matter, was carried out. Four different routes were used to prepare spinel-type NixCo3-xO4 (0 ≤ x ≤ 2.5) compounds in order to link these properties with the preparation method. The substitution of Ni for Co increases the conductivity and the porosity of the electrode till a certain ratio of nickel. X-ray diffraction patterns showed that the oxides crystallize in a cubic spinel phase. Electrical conductivity as well as porosity depends on the preparation route.
KEY WORDS: Nickel cobalt spinel oxides, Porosity, Electrical conductivity, Mixed oxides electrodes, Carbon paste electrode, Pechini sol-gel method
Bull. Chem. Soc. Ethiop. 2007, 21(2), 255-262
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