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(a) Determination of coking properties (b) The fluorine content of South African Coals and its contribution to the volatilisation of boron during combustion
(1963) Kunstmann, F
The determination of the Bonding Index, as described in the last annual report, proved to be useful test of the coking ability of a coking coal. Unfortunately, all attempts to lay down specifications for the standard anthracite, which determine its behavior in this test, failed.
Aboveground biomass subdivisions in woody species of the savanna ecosystem project study area, Nylsvley
(Cooperative Scientific Programmes: CSIR, 1979-01) Rutherford, MC
Aboveground peak season biomass is given for 11 woody species in each of five belt transects under study. Mean aerial biomass for all species was 16 273 kg ha, made up of 14 937 kg ha wood, 236 kg ha current season's twigs and 1 100 kg ha leaves with an additional 1 859 kg ha of dead wood attached to the individuals. Species which contributed most to total bioraass were Burkea africana (8 687 kg ha), Ochna pulchra (2 136 kg ha) and Tertninalia sericea (1 734 kg ha). Grewia flavescens differed from all other species in having a proportionately larger mass of dead wood and current season's twig bioraass. Shrub-sized individuals constituted 11,5% of mean total biomass and 29,7% of mean leaf mass for all species together. Values recorded in the five belt transects differed considerably, for example, leaf area index (LAI) ranged from 0,5715 in belt transect C to 1,0094 in belt transect A. The mean biomass data for the Nylsvley savanna site correspond with available biomass data for savanna vegetation elsewhere in southern Africa.
Accident rates related to rural road geometry elements and daily traffic
(National Department of Transport, South Africa, 1994-02) Skinner, DG
The available data bases for accidents, road geometry (photolog output) and traffic counts were combined and the accident rates determined for two lane, four lane and six lane road categories as well as for 22 geometric element categories. An analysis of the road kilometre distances reported for accidents was also undertaken. For some sections of road, the recording of accidents was over represented at the whole and half kilometre distance points and for other sections bridge points were over represented. The accident rates calculated for geometric elements plotted against traffic volumes gave poor correlation coefficients for linear trends. Recommendations are made for more accurate accident distance reporting.
Acclimatization Services to the Mining Industry: Statistics for 1990
(CSIR, 1991-10) Hitge, JJ; Franz, RM; Schutte, PC; Kielblock, AJ
This report is designed to convey information to mine management, environmental engineers, training personnel and acclimatization supervisors that will allow an appraisal of their mine's position with regard to heat acclimatization of workers and the incidents of heat stroke relative to mining industry in general. A total 41 mines employed heat tolerance testing and heat acclimatization of workers during 1990. Four categories of procedures are identified, namely (a) Mines where only the heat tolerance test (HTT) is performed (seven mines). (b) Mines where climatic room acclimatization (CRA) is an adjunct to the HTT (20 mines). (c) Mines where microclimate acclimatization (MCA) and CRA are used in conjunction with the HTT (12 mines). (d) Mines where only MCA is used in conjunction with HTT (two mines).
Activities of the National Programmes for Ecosystem and Aquaculture Research 1983 - 1985
(National Scientific Programmes Unit: CSIR, 1986) Auret, EW
Activities of the National Programmes for Ecosystem and Aquaculture Research of the CSIR Foundation for Research Development are reviewed, within the programmes on Inland Water Ecosystems, Terrestrial Ecosystems, Nature Conservation Research, Human Needs, Resources and the Environment and Aquaculture Research. An outline of the cooperative research activities of each section for the period July 1983 to December 1985 is presented. Several important environmental problems in South Africa amenable to solution through cooperative research by scientists from different disciplines and different scientific institutions have received attention during this period. Topics which have received significant attention and which are described in the report are: the development of limnological guidelines for the management of Southern Hemisphere inland waters; the development of a monitoring baseline for the Kuiseb environment; coastal dune ecosystems of South Africa; the ecology of biological invasions; an evaluation of rural betterment schemes; and needs for aquaculture research in South Africa
Adaptive bayesian analysis for binomial proportions
(Economic Research Southern Africa, 2008-10) Das, Sonali; Das, Sonali
The authors consider the problem of statistical inference of binomial proportions for non-matched, correlated samples, under the Bayesian framework. Such inference can arise when the same group is observed at a different number of times with the aim of testing the proportion of some trait. For example, say, we are interested to infer about the effectiveness of a certain intervention teaching strategy, by comparing proportion of ‘proficient’ teachers, before and after an intervention. The number of teachers may differ between the two measurement time points, due to any number of reasons, and thus can result in an unequal number of observations in two periods. For such nonmatched design, we develop an adaptive Bayesian method, and suggest a heuristic decision procedure to conduct statistical inference. The authors use the -divergence measure to quantify the perturbation of the posterior distribution of the proportion in different time points. They present a simulation study to compare the statistical power between the adaptive Bayesian method and the existing frequents method. Their study and theoretical results indicate that under certain design, the adaptive Bayesian method outperforms the existing method. They administer the developed adaptive Bayesian method to two case studies.
Adsorption of oxyanions of As, B, Cr, Mo and Se from coal fly ash leachates using Al3+/Fe3+modified bentonite clay
(University of Venda, 2013-01) Vhahangwele, M
South African coal-fired power stations rely on the use of low grade bituminous coal for electricity generation. During coal combustion processes, this type of coal generates large volume of waste materials which include Fly ash, bottom ash, boilers slag, flue gas desulphurization and un-captured particles. From the array of generated residues, coal fly ash constitute 90% and of this only 5% is beneficially used with the rest being disposed-off to land as ash dumps or slurried to ash retention ponds. On disposal, coal fly ash leaches out toxic chemical species on contact with the aqueous media hence posing hazardous effects to the aquatic and terrestrial environment. Of prime concern are Oxyanionic species such as As, B, Cr, Mo and Se. This study aims to investigate the adsorption of As, B, Cr, Mo and Se from coal fly ash leachates on Al3+/Fe3+ modified bentonite clay.
Adsorption of water vapour by coal
(1964) Bodenstein, L; Sevenster, PG
The study of the behaviour of moisture on coal is a rather complex one. The moisture holding capacity of coal and the ability to absorb water affects many characteristics of the material.
Adsorption swelling: A survey of the literature
(1965) Meintjies, AA
The purpose of this study is to gain an insight into one possible aspect of the problem of scaling of coal, that is the part which is played by the swelling and shrinkage of coal and coal minerals which accompany the adsorption and desorption of moisture and various atmospheric gases.
Advanced testing and characterization of transportation soils and bituminous sands
(2007-12) Anochie-Boateng, Joseph
This research study was intended to develop laboratory test procedures for advance testing and characterization of fine-grained cohesive soils and oil sand materials. The test procedures are based on typical field loading conditions and the loading characteristics of large capacity construction and mining equipment. The study also aimed to provide a better understanding of the behavior of the materials tested, and support efforts to properly model soil and oil sand behavior under both static and dynamic loads. The laboratory test results were also intended to provide both a comprehensive database of geomaterial properties that can be used to improve designs of construction and mining equipment and a set of guidelines for the future development of laboratory testing protocols and material characterization models for predicting the behavior of fine-grained cohesive soils and oil sand materials
Advances in the mordant bleaching of Karakul. Part 1: The effect of different reducing agents when mordanting with ferrous sulphate
(1987-06) Bereck, A; Trollip, NG
An investigation has been performed, the results of which provide evidence for the preferential use of phosphorus based reducing agents in place of the traditionally used sulphur based reducing agents in the first stage of mordant bleaching processes using ferrous sulphate.
Advances in understanding phosphorus cycling in inland waters - Their significance for South African limnology
(Cooperative Scientific Programmes: CSIR, 1980-02) Twinch, AJ; Breen, CM
The definitions of the different phosphorus compound fractions present in inland waters are reviewed and the limitations of the definitions discussed. The development of models of phosphorus cycling is summarized. Attempts to establish their applicability to South African inland waters have been unsuccessful. The exchange processes involved in the phosphorus cycle are influenced by the biota, by phosphorus enzymes and by the presence or absence of littoral vegetation. These processes are poorly understood, however. It is not known to what extent phosphorus exchange between sediment and water takes place in South African inland waters, but these exchange processes are influenced by the presence of a variety of soluble phosphorus fractions, dissolved oxygen and other chemical constituents in the water and by the nature of the sediments and sedimentation processes. The influence of external loading on phosphorus cycling and its significance in the prediction of algal growth is discussed. It is concluded that in South Africa factors such as shallowness, mixing and silt-loading make it desirable to study phosphorus cycling in local impoundments; existing knowledge is based primarily on deep, stratified and clear north temperate lakes. In addition, there is a need to standardize terminology and analytical techniques.
Agenda 21 for sustainable construction in developing countries: a discussion document
(CSIR, 2002) International Council for Research and Innovation in Building and Construction, CIB; United Nations Environment Programme International Environmental Technology Centre, UNEP-IETC
This discussion document “Agenda 21 for sustainable construction in developing countries” represents both a sector response and a developing country response to the challenge of sustainable development. It builds on the principles of the UN Agenda 21 formulated at the Earth Summit in Rio and is published as a contribution to the Johannesburg World Summit on Sustainable Development. The aim of this document is to provide a research and development agenda and strategy for action for construction in developing countries. This document is especially significant as it represents an important step in the empowerment of developing countries, providing as it does an agenda that was prepared entirely by experts from developing countries to answer to the specific needs and challenges of developing countries. That is, to provide developing country answers to developing country problems. However, in an interconnected and interdependent world, the Agenda 21 for Sustainable Construction in Developing Countries does not concern developing countries alone, but also offers guidance to developed countries in their pursuit of sustainability, as well as opportunities for mutually beneficial partnerships.
Agulhas Current variability determined from space: a multi-sensor approach
(2011-11) Rouault, Marjolaine J
Satellite remote sensing datasets including more than 6 years of high frequency Sea Surface Temperature (SST) imagery as well as surface current observations derived from 18 years of merged-altimetry and over 2 years of Advanced Synthetic Aperture Radar (ASAR) observations are combined to study the variability of the Agulhas Current. The newly available rangedirected surface currents velocities from ASAR, which rely on the careful analysis of the measured Doppler shift, show strong promise for monitoring the meso to sub-mesoscale features of the surface circulation. While the accuracy of ASAR surface current velocities suffers from occasional bias due to our current inability to systematically account for the wind-induced contribution to the Doppler shift signal, the ASAR surface current velocities are able to consistently highlight regions of strong current and shear. The synaptic nature and relatively high resolution of ASAR acquisitions make the ASAR derived current velocities a good complement to altimetry for the study of sub-mesoscale processes and western boundary current dynamics. Time-averaged range-directed surface currents derived from ASAR provide an improved map of the mean Agulhas Current flow, clearly showing the location of the Agulhas Current core over the 1000 m isobath and identifying the region at the shelf edge of the north-eastern Agulhas Bank as one of the most variable within the Agulhas Current. To determine the variability of the Agulhas Current, an algorithm to track the position of the current is developed and applied to the longer merged-altimetry and SST records.
Alien invasive vascular plants in South African natural and semi-natural environments : bibliography from 1830
(Cooperative Scientific Programmes: CSIR, 1982-12) Moran, VC; Moran, PM
A compilation of references to research on alien invasive plants in South Africa is given. Crop weeds and indigenous plants are not included. Reference is made to 457 publications. Keyword listings and a keyword index are provided.
An alternative approach to mass balances in coal washing plant performance tests
(1977) Savage, WHD
In many tests the separating bath is fed with coal covering a wide range of sizes. This note is based on a study of data contained in FRI report No. 44 of 1977.
Alternative fuels for internal combustion engines. Document 3/1
(1966) Van Doornum, GAW; Gericke, EL
This report forms part of a three part series, investigating alternative fuels for engines.
Analyses of samples from boreholes 2 and 3 on "Bankfontein 503" near Uitkyk, Transvaal
(1936) Hall, PE
These two borehole were sunk by the Minnaar-Witbank Colliery during February 1936.
The analysis of oils from the hydrogenation and supercritical gas extraction
(1976) Kershaw, JR
The oils from dynamic and static hydrogenation, supercritical gas extraction and soxhlet extraction were separated into a number of fractions by absorption chromatography on silica-gel. The fractions from this chromatographic separation were investigated by ultra-violet and infra-red spectroscopy and gas chromatography. The chemical nature of the compounds are discusses, and compared and contrasted between the various processes.
Analysis of product samples taken by the Fuel Research Institute during 1972
(1972) Savage, WHD
In Bulletin No 76, which gave average data for 1971, it was mentioned that Enyati and Vaalbank collieries ceased production during that year.

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