The Use of South African Fe-Mn, Si-Mn, Pt-Converter and Matte-Smelting Furnace Slags in Composite Portland Cement - First Results

Author(s):  
Sabine M. C. Verryn ◽  
Herbert Pöllmann ◽  
Elsabé Kearsley
2006 ◽  
Vol 5 (3) ◽  
pp. 183-186
Author(s):  
R.A. Street ◽  
D.J. Christian ◽  
W.I. Clarkson ◽  
A.C. Cameron ◽  
B. Enoch ◽  
...  

The WASP consortium is conducting an ultra-wide field survey of stars between 8–15 mag from both hemispheres. Our primary science goal is to detect extra-solar ‘hot-Jupiter’-type planets that eclipse (or transit) bright host stars and for which further detailed investigation will be possible. We summarize the design of the SuperWASP instruments and describe the first results from our northern station SW-N, sited in La Palma, Canary Islands. Our second station, which began operations this year, is located at the South African Astronomical Observatory. Between April and September, 2004, SW-N continuously observed ~6.7 million stars. The consortium's custom-written, fully automated data reduction pipeline has been used to process these data, and the information is now stored in the project archive, held by the Leicester database and archive service (LEDAS). We have applied a sophisticated, automated algorithm to identify the low-amplitude (~0.01 mag), brief (~few hours) signatures of transiting exoplanets. In addition, we have assessed each candidate in the light of all available catalogue information in order to reject data artefacts and astrophysical false positive detections. The highest priority candidates are currently being subjected to further observations in order to select the true planets. Once the exoplanets are confirmed, a host of exciting opportunities are open to us. In this paper, we describe two techniques that exploit the transits in order to detect other objects within the same system. The first involves determining precise epochs for a sequence of transit events in order to detect the small timing variations caused by the gravitational pull of other planets in the same system. The second method employs ultra-high precision photometry of the transits to detect the deviations caused by the presence of exoplanetary moons. Both of these techniques are capable of detecting objects the size of terrestrial planets.


Author(s):  
Shawren Singh ◽  
Goonasagree Naidoo

With the rapid technological development, electronic governance is a justifiable reality. In this chapter we look at the unique environment under which the South African electronic government is developing. The purpose of this chapter is to report on the first results towards the establishment of an e-government strategy for South African, considering its multicultural and multilingual society.


2011 ◽  
Vol 71-78 ◽  
pp. 2239-2242 ◽  
Author(s):  
Hai Yu ◽  
Lian Yong Wang ◽  
Tao Du

In the paper, we take current relatively advanced, the most widely used flash smelting furnace, converter and rotary anode furnace as the examples, the waste heat resources of the process of matte smelting, the process of matte converting and the process of fire refining of blister copper in copper pyrometallurgy are analyzed respectively. Meanwhile, based on the way of using waste heat reasonably to suitable heat consumer in production process and the grade recovery principle of energy level matching, the model of waste heat recovery and reuse of flue gas in copper pyrometallurgy is constructed.


2014 ◽  
Vol 600 ◽  
pp. 215-224 ◽  
Author(s):  
Leandro Santos de Oliveira ◽  
Normando Perazzo Barbosa ◽  
Fabiana Silva Santos ◽  
Carlos Maviael de Carvalho

Stabilization is important in earthen construction in order to improve mechanical strength, volumetric stability, workability and even ductility. Currently, the products used to stabilize the earth are lime, Portland cement and bitumen emulsions. Due to the environmental problems that the mankind faces nowadays, the use of earthen construction is increasing. Adobe is the most traditional type of block used in masonry. To improve strength against water, a new way to stabilize this kind of unburned earth block is proposed by the alkaline activation of earth. This paper presents the first results about the experimentation made in the stabilization of soil with alkali activator. Two cure temperatures were tested: room temperature and oven at 50°C. The amounts of stabilizer used were 3% and 6% activator by mass of earth. Results show that it is possible for adobe blocks to be resistant to water action using the alkaline activation.


1976 ◽  
Vol 32 ◽  
pp. 577-588
Author(s):  
C. Mégessier ◽  
V. Khokhlova ◽  
T. Ryabchikova

My talk will be on the oblique rotator model which was first proposed by Stibbs (1950), and since received success and further developments. I shall present two different attempts at describing a star according to this model and the first results obtained in the framework of a Russian-French collaboration in order to test the precision of the two methods. The aim is to give the best possible representation of the element distributions on the Ap stellar surfaces. The first method is the mathematical formulation proposed by Deutsch (1958-1970) and applied by Deutsch (1958) to HD 125248, by Pyper (1969) to α2CVn and by Mégessier (1975) to 108 Aqr. The other one was proposed by Khokhlova (1974) and used by her group.


1976 ◽  
Vol 32 ◽  
pp. 109-116 ◽  
Author(s):  
S. Vauclair

This paper gives the first results of a work in progress, in collaboration with G. Michaud and G. Vauclair. It is a first attempt to compute the effects of meridional circulation and turbulence on diffusion processes in stellar envelopes. Computations have been made for a 2 Mʘstar, which lies in the Am - δ Scuti region of the HR diagram.Let us recall that in Am stars diffusion cannot occur between the two outer convection zones, contrary to what was assumed by Watson (1970, 1971) and Smith (1971), since they are linked by overshooting (Latour, 1972; Toomre et al., 1975). But diffusion may occur at the bottom of the second convection zone. According to Vauclair et al. (1974), the second convection zone, due to He II ionization, disappears after a time equal to the helium diffusion time, and then diffusion may happen at the bottom of the first convection zone, so that the arguments by Watson and Smith are preserved.


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