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By M. K. G. Vermaak

There are practical indications that flotation recovery of palladium bismuth tellurides is poor. This work tested whether this can be caused by a lack of interaction of the collector with the telluride. Impedance measurements, voltammetry and Raman spectroscopy were performed to determine the interaction of dithiocarbonate collectors (KEX) with Pd-Bi-Te. Impedance measurements showed lower capacitance values in solutions containing KEX, indicating the formation of a continuous surface layer. Anodic and cathodic polarization diagrams show the mixed potential to be higher than the reversible potential of the xanthate-dixanthogen equilibrium reaction; hence the formation of dixanthogen on the surface is possible. Electrochemically controlled in situ Raman spectroscopy did indicate the presence of bulk diethyl dixanthogen on the surface. Raman spectroscopy has confirmed the co-presence of xanthate with dixanthogen, indicating that xanthate retains its molecular integrity when it adsorbs on the surface of the Pd-Bi-Te. As a result, the mineral surface is expected to be hydrophobic and alack of collector interaction with the mineral is not the reason for the low PGM recoveries experienced. Keywords: Raman spectroscopy; Pd-Bi-Te; ethyl xanthate; platinum flotation; Great Dyke; Pd-bearing bismutho-tellurides and moncheite.

Jan 1, 2004

By M. L. Smith, G. Karunatillake

Lead-zinc production at MIM, Mount Isa includes three mines, a lead concentrator, zinc filter plant and lead refinery. Lead production is vertically integrated with lead-silver bullion shipped from Australia to London for refining. Zinc is sold as a concentrate. All three mines have reached varying states of maturity mining a multitude of orebodies having significant variation in grades and metallurgical recovery for three metals. Based on current levels of measured resources, the remaining project life is at least ten years. The objective is to schedule production over the life of all three mines so as to maximize the present value of the complex. Additional scheduling complexity arises out of the implementation of long-term schedules, capital expansion projects for both mining and processing, the presence of substantial inferred reserves and interactions with MIM copper production. A large-scale, time-dynamic, life-of-complex Mixed Integer Program (MIP) production schedule was formulated to optimize lead/zinc cash flow based on a detailed life of project production scheduling study. The requirements for such a study are detailed herein. The operational feasibility of the MIP solution is compared against a non-optimal approach to strategic life-of-mine scheduling. The strategic planning emphasis placed on the MIP is compared to the implementation of a life-of-mine schedules at Mount Isa using spreadsheets and other popular commercial mine schedulers.

Jan 1, 2003

By D. -H. Park, G. -j. Kim, Y. -J. Park, C. -S. Hong, S. -Y. Choo

To evaluate the quantitative tunnel behavior influenced by characteristics of discontinuity, this pa-per executes the parametric study using 2 and 3-dimensional DEM analysis. First of all, this study finds that displacement and the stress of shortcrete are proportioned to frequency of joint and rockbolt axial force is adversely proportioned too. Secondly, it is found that the most sensitive in-put parameter used in Barton-Bandis(BB) model is residual friction angle. Finally, when joint sets are encountered at tunnel excavation face, to identify the most critical joint orientation is very crucial for a stability of tunnel. La thèse a pour but d’étudier les influences sur la stabilité du tunnel, au niveau du réseau de la discontinuité et de la valeur de sa nature aquis par le projet récemment exécuté en vue de mener à l’analyse quantitative de cette stabilité, en appliquant chaque différent paramètre comme la fréquence de diaclase, la constante de résistance des modèles de Barton-Bandis(BB) ainsi que la relation entre le sens d’excavation du tunnel et le réseau de diaclase en 3 dimensions. En fait, cette étude nous a montré que la fréquence de diaclase s’accroît proportionnellement au déplacement et à la contrainte du béton projeté. L’angle de friction résiduel s’est montré le plus sensible à la stabilité du tunnel parmi les modèles de BB. Aussi à travers l’analyse à 3 dimensions, il s’est vérifié que si l’angle de pente du groupe de diaclase est horizontal entre l’axe du tunnel et la direction, il donne une influence importante sur le comportement du tunnel. En particulier, l’influence était la plus importante sur un fond rocheux dont la diaclase horizontale est grande. Um das quantitative Verhalten des Tunnels zu bewerten, eroertert dieses Papier eine parametrische Studie mit Hilfe der DEM Analyse. Auch wird hier eine zweidimensionale Analyse von Ver-bindungen verschiedener Frequenzen in der Gesteinsmasse, eine sensitive Analyse von allen der im Barton-Bandis-Modell (BB) genutzten Parameter und eine Dreidimensional-Analyse mit ver-schiedenen dreidimensionalen geometrischen Veteilungen von Verbindungen ausgefuehrt. Erstens: Die Studie findet heraus, dass Vedraengung und Druck im Shortcrete proportional zur Frequenz von Verbindungen und Axialkraft der Steinbolzen antiproportinal ist. Zweitens: Es wird herausge-funden, dass die am meisten Sensitiven der im BB-Modell angewendeten Eingaben die am Ende uebriggebliebenen Reibungswinkel sind. Und schliesslich wird herausgefunden, dass wenn Ver-bindungsteile an der Tunnelaushoelungsoberflaeche ausgemacht werden, fuer die Tunnelstabiltaet die Identifikation der meist kritischen Verbindungsorientierung sehr bedeutungsvoll.

Jan 1, 2003

By T. Plikas, L. H. Gunnewiek, L. Oshinowo

Electric furnace smelting is one of the principal unit operations for ferroalloy production, and increased process intensity, improved availability, minimal maintenance and a longer campaign life are common objectives for electric furnace operation in order to obtain favourable economics of production. Furnace designers have continued to develop innovative solutions that have allowed these objectives to be realised, e.g., furnace cooling systems, and numerical modelling plays a key role in the design process. Enhanced understanding of the energy transfer process in the furnace and the ability to develop, evaluate and optimise components of the crucible design to match process requirements are the key motivators for modelling. This paper provides an overview of recent applications of numerical modelling to the design of electric furnaces. The aim is to illustrate what can be done, and identify areas where further work is needed in this field. Examples include furnace bath modelling, crucible cooling system design, taphole design, baking of Soderberg electrodes, off-gas systems, and fume control and building ventilation. It is argued that the trend is for numerical models to become more encompassing while at the same time more accessible, and therefore further improvements in furnace design will be realised with continued and well validated modelling efforts.

Jan 1, 2004

By J. D. Steenkamp

In a paper presented at the Heavy Minerals Conference 2001 a laboratory scale investigation on the beneficiation of an ilmenite containing waste stream by magnetizing roasting was reported1.This waste stream contained a high concentration of ilmenite, which was contaminated by chromite and other gangue minerals. Interpretation of the results of the investigation was based on the assumption that during magnetizing roasting of an ilmenite concentrate, under the oxidizing conditions, the magnetic properties of the chromite would remain constant. In this article thefollowing hypothesis was tested: The magnetic susceptibility of chromite would remain constant during magnetizing roasting of an ilmenite concentrate under the oxidizing conditions reported by Gouws and Van Dyk1. The results of this study indicated that the hypothesis is not true. The increase in the magnetic susceptibility is not significant though and it is expected that it will not influence the final ilmenite quality to a large extent. Based on the assumptions that the bulk magnetic susceptibility of the waste stream samples represents that of the ilmenite in the waste stream, and the bulk magnetic susceptibility of UG1 chromite that of the of chromite in the waste stream, the results also served to confirm that the waste stream with a high chromite content should be roasted under oxidizing conditions, in a reactor with a well-defined retention time distribution (i.e. a fluidized bed reactor), at a roasting temperature of 750°C (rather than the higher temperature ranges of 800°C and 850°C).

Jan 1, 2003

By L. Sahu, S. Bhattacharya, S. Dey

"An ideal procedure to determine the limits of flotation-based separation, as is the case with washability analysis for density separation, does not exist. Therefore, a procedure called release analysis, considered to be the counterpart of the washability process in density separation, was developed to evaluate the flotation characteristics of coal fines. Since flotation is a complex process it is necessary to know the maximum recoverable yield that could be achieved at a target ash level and what could be obtained by release analysis. Due to a number of limitations in the initial procedures, modifications were recommended by various researchers to generate an optimum separation curve. This paper presents a review of, and a discussion on, the chronological evolution of release analysis methodology over the decades. Notwithstanding the availability of a standardized release analysis procedure, such as BS 7530, the paper highlights the critical parameters involved in the procedures, such as coal type, feed characteristics, choice of reagents and dosage, operator bias, and design features of the flotation cell IntroductionCoal is a heterogeneous substance consisting of various combustible constituents (macerals) and associated mineral matter. The kind and abundance of the various macerals present in the coal, such as vitrinite, semivitrinite, exinite, and inertinite, determine the type of coal. As macerals are formed by biological degradation of different parts of the plant material, they have different properties based on their original composition. Coal cleaning processes are dependent on the differences in physical properties between the coal components (the macerals) and also between the macerals and the mineral matter. Thus the cleaning characteristics of the coal might vary from one type to the next. The cleaning processes influence the distribution and the concentration of macerals in the various size and density fractions of the cleaned product."

Jun 1, 2019

What is a nugget effect? In the early development of geostatistics, the term ?nugget effect? was coined for the apparent discontinuity at the beginning of many semivariogram graphs. This name was chosen to reflect the large differences found between neighbouring samples in ?nuggety? mineralizations such as Wits gold reefs. Geostatistical theory assumes that the difference between a sampled value and a potential repeat sample at the same location is actually zero. Included in this ?nugget effect? would be true variation between contiguous samples due to the nature of the mineralization, micro-fracturing, nugget or crystal size, and so on. Also included in the nugget effect would be any ?random? sampling variation which might occur due to the method in which the sample was taken, the adequacy of the sample size, the assaying process, etc. Arguments were put forward that ?sampling errors? actually exist at zero distance. Some geostatistical schools actually maintain that the ?nugget effect? is all sampling error. This would imply that ?perfect? sampling would eliminate the nugget effect entirely. There is now a dichotomy both in the geostatistical world and in the software packages provided for geostatistical analyses. It may seem academic to argue over whether the semivariogram model should take a value of zero, a value equal to the nugget effect, or a partial value at distance zero. However, the decision can have a profound effect on both the estimated resource and in our confidence on that resource. Whereas most geostatistical texts define the semivariogram model as taking the value of zero at zero distance, others imply that the full nugget effect should be used at zero distance. For example: ?The nugget effect refers to the nonzero intercept of the variogram and is an overall estimate of error caused by measurement inaccuracy and environmental variability occurring at fine enough scales to be unresolved by the sampling interval3 ?Christensen4 has shown that the ?nugget effect?, or non-zero variance at the origin of the sernivariogram, can be reproduced by a measurement error model ?The nugget effect is considered random noise and may represent short-scale variability, measurement error, sample rate, etc.5. In many training texts and Web courses, the definition of the semivariogram is ambiguous as the formulae for semivariogram models is not actually specified at zero distance6,7,8.

Jan 1, 2010

By R. G. Tarr

During an intense and accurate study of initiation systems used on an AngloGold mine, Mine A, poor drilling practices were revealed. Graphic results of all actual measurements taken are shown below. [ ] Accurate drilling of shot holes will determine whether a mining operation is payable or not and at what pay limit mining can take place. Losing 30 cm of a potential 120 cm-hole length will result in a number of consequences, i.e.: ?Higher stoping costs ?Drilling of one shot hole twice in every five shifts ?Increased explosive cost as a result ?Excess stress on hangingwall and footwall due to bad face shape ?Excessive blast damage before the area is worked out. No wonder we have such a high-risk operation. Drilling accuracy is crucial to the profitability on any mine as profits are directly related to the quality and utilization of the drilled shot holes.

Jan 1, 2000

By P. Mbele

Iron ore concentrate is not easily transported to, or processed in, ironmaking plants, therefore it is necessary to agglomerate. This paper will determine the possibility of agglomerating Sishen concentrate into suitable ironmaking feedstock. Pelletizing is one of the conventional and preferred agglomeration processes for iron ore concentrate investigated at Kumba Value-In-Use Laboratories. Sishen concentrate was mixed with binder, and then pelletized using a laboratory pelletizing disc; afterwards the green pellets were indurated at high temperatures to give strength high enough to survive handling and lessen disintegration in the shaft during ironmaking. Sishen pellets have satisfactory physical and metallurgical properties which make them suitable feedstock for the direct reduction processes. These were tested under Midrex shaft operational conditions and performed well, with a metallization of 94.47% being attained.

Jan 1, 2012

By R. Thomas

A Honeywell TDC 2000 central process control system was installed at Rössing in 1984. The system controls the metallurgical operations from crushing to the finished product of uranium oxide and manufacture of sulphuric acid. The operation was previously controlled from nine separate local control rooms. The paper briefly reviews the design and commissioning of the control system on an operating plant and discusses the impact on manpower organisation and training needs. Development of the process control system during its first two years of operation is reviewed and a summary is given of the current status of computer control at Rössing. The impact of the new system on overall plant operation and performance efficiency is also briefly described. In conclusion, future developments of computer control and overall optimisation of metallurgical operations are reviewed.

Jan 1, 1987

By A. Kijko, C. W. Funk

Methods for the analysis of seismic hazards in mines are reviewed as illustrations of the techniques that are being used in some South African mines. The classical parameters that describe a hazard are the seismic activity rate, ?, the Gutenberg-Richter value, b, and, occasionally, the maximum regional magnitude, mmax The activity rate is calculated readily owing to the inherent simplicity of its definition. The evaluation method presented for the Gutenberg-Richter b value takes into account the presence of mmax Three statistical procedures are described for the assessment of mmax which the maximum observed magnitude, Xmax a crucial role. Often, the configuration of mine seismic networks is changed, or the networks are improved, which inevitably gives rise to changes in the completeness of the seismic catalogues. The routine analysis of seismic hazards must account for these time dependent changes. A method for the evaluation of hazards is reviewed that accommodates varying levels of quality in the catalogues. Finally, the concept of the volume of ground motion (VGM) is presented. This is a technique that allows for most aspects of seismic hazards in mines. The advantage of the VGM is that a hazard can be described by one physically significant value: the volume of rock (cumulated over a time period) in which the ground motion exceeds some critical particle velocity. Data from the gold mining region in South Africa known as the Far West Rand is used in a demonstration of the discussed methods of hazard analysis.

Jan 1, 1994

By Y. Rao, Y. Huang, G. Wang, W. Liu

The properties and deterioration in strength of cemented tailings backfill (CTB )in the underground acidic environment under oxidizing conditions were studied. X-ray diffraction analysis and scanning electron microscopy of the surface of the CTB was carried out, and the sulphuric acid corrosion mechanism elucidated. The properties tested included compressive strength, elastic modulus, cohesion, internal friction angle, variation in the hydrogen ion concentration, and stress-strain relationship in different corrosion periods. The damage model of the CTB was established considering the effects of parameters such as corrosion time and strain on the damage evolution. It was found that the compressive strength, elastic modulus, cohesion (binder effect), and internal friction angle increased at first and then decreased with exposure time. In the long term, the peak stress decreased with corrosion time while the peak strain increased; elastic modulus, and deformation modulus also decreased. The damage caused by corrosion and by load were related by means of a mathematical model, which revealed the relationships between sulphuric attack, load, and damage to backfill in complex underground environments. During corrosion, the expansion of gypsum and ettringite caused microfractures in the CTB. With increasing corrosion time, micro-cracks developed and proliferated. The mechanism of corrosion damage was found to be the dissolution of hydrogen ions and a sulphate ion reaction that produces an expansive substance, resulting in deterioration of the strength of CTB.

Jun 1, 2021

By G. van den Berg

Anglo Platinum has initiated a project to investigate hydraulic hoisting technology for platinum mines. Hydraulic hoisting systems are categorized as pumping, fluidizing feeder or displacement feeder systems. Positive displacement piston diaphragm pumps are most suitable for pumping systems but they require that the ore be milled prior to pumping. Fluidizing feeders are unsuitable for platinum ore applications due to the large percentage of fines in the ore. The three-chamber pipe displacement feeder has been most widely used for hydraulic hoisting and is the most suitable technology for platinum mines. Eight hydraulic hoisting applications covering pumping and displacement feeder technologies are reviewed. The key factors to be assessed in selecting a hydraulic hoisting system for a platinum mine are discussed. A typical platinum mine configuration will comprise an ore preparation plant (to produce -15mm material through screening or crushing), motive water pump on surface, high pressure water pipeline from surface to underground, ore slurrification plant, three-chamber displacement feeder, and a high pressure slurry pipeline to surface. The water and slurry pipelines are housed in a purpose drilled borehole. A hydraulic hoisting system selection chart is presented. A 150mm diameter system with a 25 MPa pressure rating is required to hoist 60 000 t/m from a depth of 1 200 m. Generic capital and operating costs are presented. A major potential advantage of hydraulic hoisting is that the fines, which contain a high percentage of PGMs, are captured underground and transported directly to the concentrator. Hydraulic hoisting technology is ideally suited to providing supplementary hoisting capacity to existing shafts that have reached the skip hoisting capacity limit. The main advantage for new shafts is the potential to significantly simplify underground rock handling and transportation. All hydraulic hoisting system components are proven. The only risk area is the wear rates of the valves and piping. Current estimates are based on gold ore. The business cases investigated show that the financial viability of the installations are not sensitive to wear rate. Hydraulic hoisting is technically feasible and financially attractive for platinum mines. Keywords: hydraulic hoisting, slurry

Jan 1, 2005

When designing coal mine roof support, it is necessary to account for the uncertainties and variability that inherently exist within the rock mass and support elements. The performance of a support system is affected by these uncertainties, which are not taken into account in the current deterministic design methodologies used in South Africa. The key to the design of a roof support system is a better understanding of roof behaviour and uncertainties that can been countered during extraction. This paper sets out to develop a method that takes all uncertainties that exist within the rock mass and the mining process into account and provides a quantitative risk-based design methodology.

Jan 1, 2009

By D Reddy

Rosh Pinah Zinc Corporation is a zinc-lead mine located in southern of Namibia. It is currently considering the development of a low grade ore body containing about 2.8% zinc. This ore can be utilised by the concentrator if it could be upgraded prior to the ball mill. Preliminary work indicated that the ore may be upgraded in a pre-beneficiating stage by using dense medium separation, X-ray sorting or a combination thereof to a feed grade of minimum 9% zinc. This paper describes the process followed in evaluating the technologies for pre-beneficiation. The results from test work indicated that the low grade ore is amenable to pre-beneficiation by both dense medium separation and X-ray sorting. A comparison between the two technologies showed that dense medium separation marginally outperformed X-ray sorting on grade and recovery. The results for the X-ray sorting were achieved by tuning the calibration curve specifically for the samples tested.

Jan 1, 2008

By C. H. Johannes, N. B. Strydom, C. H. Van Graan, J. G. A. Van Heerden

Note: The practical application of microclimate cooling in an underground stope in a gold mine by C. H. JOHANNES, C. H. VAN GRAAN, N. B. STRYDOM and J. G. A. VAN HEERDEN INTRODUCTION Although much information was available on the use of pre-frozen jackets as micro climate coolers in underground situations!, 2, no information was available on their performance under practical conditions in stopes. The objectives of this study were. O.F .S. Branch Minutes of the General Meeting held in the upstairs lounge at the Harmony Country Club, Harmony G.M. Co. limited, on Wednesday 12th November, 1975 at 4.00 p.m. NIM reports Report no. 343 A mineralogical investigation of gold-bearing sulphidic ore from the Florence-Devonian Mine, Barberton.(20th May, 1968; re-issued Dec. 1975). Report no. 1384 . Flotation tests on samples of Canadian copper-zinc ores. (12th Nov., 1971; re-issued Nov. 1975). The results are given of laboratory Report no. 1488 Extraction of rutile from Highveld smelter slags. (28th Sep., 1972; re. issued Nov., 1975). Report no. 1499 The production of medium -carbon ferrochromi'um. (4th Dec., 1972; reissued Nov. 1975). Report no. 1521 The dissipation of electrical power in the burden of a submerged-arc furnace. (15th Feb., 1973; re-issued Nov. 1975). Report no. 1527 The physicochemical properties of slags associated with the smelting of nickel sulphide concentrates. (21st Feb., 1973; re-issued Nov. 1975). Report no. 1544 The recovery of salable ferrochromium from material discarded by Ferrometals Limited. (11th Jun., 1973; re-issued Nov. 1975). Report no. 1547 Physicochemical and thermodynamic properties of slags in the system MgO-AlOl.5SiO2. (23rd Aug., 1973; re-issued Nov. 1975). Report no. 1548 Physicochemical properties of slags in the system MgO-Al2O3-SiO2 and their application to the technology of ferro-alloy smelting. (13th Jul., 1973; re-issued Nov. 1975). Report no. 1553 Characterization of the flotation properties of fluorspar from smallscale batch and pilotplant tests. (27th Sep., 1973; re-issued Nov. 1975). Report no. 1555 The analysis, by atomic-absorption spectrophotometry, of matte-leach residues. (2nd Oct., 1973; re-issued Nov. 1975). Report no. 1590 The separation of osmium from ruthenium in hydrochloric acid solutions. (18th Jan., 1974; re-issued Oct. 1975.) Report no. 1606 The electrical-resistance characteristics of the charge in the electric reduction furnace. (1st Feb., 1974; re-issued Oct. 1975). Report no. 1622 The electrical conductivity of the charge in a ferrosilicon furnace. (2nd Apr., 1974; reissued Oct. 1975).

Jan 3, 1976

By P. A. Roberts

A modified in situ leaching method for extracting gold from oxidized gold ores using a non cyanide lixiviant is proposed. A non cyanide lixiviant is suggested because of the obvious concerns posed by injecting cyanide bearing solutions into the subsurface. Oxidized gold ores are the initial focus because earlier research on the use of sodium thiosulphate as a lixiviant under anaerobic conditions indicated that the presence of pyrite led to rapid thiosulphate breakdown. A reconnaissance research programme, involving ore characterization and hydrometallurgical testwork on samples from four Australian ore deposits and preliminary reactive transport modelling studies was carried out. This work showed that lixiviant-oxidant combinations of sodium thiosulphate and ferric EDTA, and iodide and iodine are both capable of extracting high percentages of accessible gold from the selected samples under anaerobic conditions. The ore characterization and reactive transport studies, suggested that both physical and chemical methods of permeability enhancement may be required to lift bulk permeability and the availability of gold for dissolution to sufficiently high levels to obtain adequate gold recoveries. Physical permeability enhancement could be achieved by blasting and/or hydraulic fracturing of the ore. Assuming that such methods prove to be both necessary and economically viable, the mining method would no longer be regarded as simple in situ leaching. Therefore, the term ?in place leaching? has been adopted for the proposed gold extraction system

Jan 1, 2009

By M. J. Lukhele

Paper written on project work carried out in partial fulfilment of B. Tech (Mining Engineering) degree A number of high wall mining methods were developed over the years to mine coal reserves exposed on the high walls created during surface mining. The auger mining system was initially developed in the early 1940s in the United States of America. High wall mining is a method of recovering coal from seam exposed either by mechanical excavation methods or natural erosions. This is usually associated with strip-mining (opencast) where the stripping ratio is high and uneconomical to mine using the opencast mining method. This paper discusses the surface auger mining as deployed at Rietspruit Mine Services Proprietary Limited.

Jan 1, 2002

The practice of pumping gases which inhibit combustion for purposes of controlling or extinguishing mine fires is now universally accepted. The practice has been used many times in coal mines in India and the experiences are reviewed. The procedures relating to a membrane based nitrogen generator and to a combustion gases generator are described. The physical properties, practical requirements and economic implications of using different gases is briefly reviewed. Some aspects of the practice as related to mine fires in certain collieries in other countries are dealt with.

Jan 1, 2000

By Du Sichen, K. Mukai, S. Seetharaman

Viscosities of slags constitute an important physical property needed for an understanding of the mass transfer phenomena in metallurgical processes. Viscosity is also the key that leads to a better understanding of the structure of slags. It is well known that the viscosities of silicate slags decrease with the addition of basic oxides due to the breaking of the silicate network. The measurements of slag viscosities often pose experimental challenges, especially to the choice of materials. The keynote lecture takes up the experimental problems and the various techniques adopted. Dynamic viscosity measurement, as a powerful tool towards an understanding of the kinetics of some high temperature reactions, is brought out. A number of semi-empirical models have been developed to estimate the slag viscosities in the case of multi component slags. A critical survey of these models is presented in the lecture. Earlier models by Riboud et al., Urbain et al. and Mills et al. have been developed further into a new generation of models. Some of the current important models are (1) Model by Iida et al. (2)CSIRO model (3) Pyro research Model (4) Model by Tanaka et al. (5) Model approach by Reddy et al. and (6) KTH-model. The predictions and capabilities of the various models are compared. Estimations of viscosities from thermodynamic data and prediction of liquidus temperatures from viscosities are presented. The concept of surface viscosities with reference to slags and viscosities of two-phase mixtures are also taken up in the presentation.

Jan 1, 2004