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In the last decade important results have been achieved with the usage of geostatistical methods for the solution of geologic and mining problems, particularly in the estimate process of resources in Cuban lateritic deposits. Their uses imply on the one hand, to master fundamental concepts such as: the semivariogram calculation and adjustment, the kriging estimate and the geostatistical simulation, on the other hand, it is necessary to carry out a suitable processing interpretation in each moment, which depends on the experience of specialists on the subject. In this paper, some comments are presented on the article Geostatistical models of the nickel concentration in the domain 7 of Punta Gorda deposit with regard to the geostatistical simulation. [ABSTRACT FROM AUTHOR]

Mining is an activity that causes considerable damage to ecosystems. This paper aims to argue the convenience of generalizing the implementation of rehabilitation procedures for open-pit mined areas with a socioenvironmental and economic approach, which is essential to make sustainable development viable. The recommended procedure to be generalized incorporates novel elements in the social, environmental and economic dimensions whose effects transcend the rehabilitation of the affected ecosystem and generate impacts that contribute to sustainability in the broadest sense. [ABSTRACT FROM AUTHOR]

Kaolinitic clays have broad prospects in cement production and as a source of pozzolanic materials. The present paper focused on the petrographic and mineragraphic analysis of the Dumañuecos kaolinitic clay deposit, in the municipality of Manatí, Las Tunas province. In the petrographic and mineragraphic characterization of the rocks, polarized light and reflected light microscopy were used. Petrographic analysis revealed the presence of quartz, feldspars and tourmalines; as well as the predominance of granoblastic and cataclastic textures. It was established, through mineragraphic analysis, that the main mineralogical association is quartz + hematite + goethite + pyrite and cement and zonal textures predominate. The occurrence of feldspar spherules with a fibrous-radial internal structure and traces of feldspar phenocrysts indicate the possibility that the source rock of the reservoir is lava with a rhyolitic composition. [ABSTRACT FROM AUTHOR]

Cojímar Formation, --Lower Miocene (upper part) to Middle Miocene (lower part)--, is a unit in Western Cuba well known for its extensive development and exposure outcrops. It has been widely used in bioestratigraphic studies. However, paleoecological studies on this unit through foraminifera, both planktonic and benthic species, are considered insufficient. The richness and variety of microfossils, especially foraminifera, has allowed us to address the paleoecological aspect. In this paper, the sedimentary environment is established. Besides the systematic classification of these species was updated and the biozonation re-evaluated from planktonic foraminifera. A detailed sampling, from material taken every 15 meters was fulfilled along with a compilation of all species of foraminifera reported for the studied unit. The micropalaeontological analysis allowed the identification of 40 taxa of planktonic foraminifera grouped into 12 genera, being the most representative Globigerina, Globigerinoides, Orbulina, and Globorotalia. Moreover, 226 taxa of benthic foraminifera belonging to 102 genera were determined. These included: Lituolida, Loftusiida, Textulariida, Lagenida, Rotaliida and Miliolida suborders. The main genres represented were Cibicides, Cibicidoides, Cibicobis, Uvigerina, Angulogerina, Anomalinoides, Planulina, Bolivina, Amphistegina, Lenticulina, Nodosaria, and Textularia. Cojímar Formation corresponds to a deep platform, which was determined from the benthic microforaminifera (Uvigerina, Lenticulina, Marginulina) analyzed. Thanatocenoses developed in outer neritic to upper bathyal depths between 100 m - 500m. New reports of both planktonic foraminifera species for that unit as small benthic, such as Anomalinoides flintii, A. trinitatensis, Planulina valued cf. P. mantaensis, Catapsydrax cf. C. dissimilis, Globigerinoides cf. G. obliquus, Globigerinoides primordius, and Hastigerina praesiphonifera were evaluated. As a contribution Gyroidinoides cibaoensis taxon is here first reported to Cuba. [ABSTRACT FROM AUTHOR]

Modeling safety scenarios for dams strengthens effectiveness of disaster risk management plans in this kind of work by reducing risk of failures that can cause considerable damage. The aim of the present paper was a proposal of a modeling methodology for safety scenarios in tailing dams from the Cuban nickel industry, to determine indicators and failure mechanisms, in order to achieve early detection risks and their reduction, as well as to minimize the negative impacts on the economy, the population, and the environment through a risk and disaster management plan. [ABSTRACT FROM AUTHOR]

The article aims to clarify how the deep sea tailings depositions have been used worldwide as alternative mining practice. The paper is a checking of case studies where this technology is used. The available information sources were consulted, which included: case reports, scientific papers, theses and reports by proper authorities. It is achieved to expose the fundamental principles of operation and environmental impact of this technology in the marine environment by applying empirical methods and theoretical research, as well as an assessment of main cases in the world. [ABSTRACT FROM AUTHOR]

Modeling safety scenarios for dams strengthens effectiveness of disaster risk management plans in this kind of work by reducing risk of failures that can cause considerable damage. The aim of the present paper was a proposal of a modeling methodology for safety scenarios in tailing dams from the Cuban nickel industry, to determine indicators and failure mechanisms, in order to achieve early detection risks and their reduction, as well as to minimize the negative impacts on the economy, the population, and the environment through a risk and disaster management plan. [ABSTRACT FROM AUTHOR]

This paper presents a multivariate UPD estimator, family member [A,U,T] with parameters p and s, which allows to calculate simultaneously parameters of Weibull K and C at a point Pe from the measured values of these variables in several sampling points. During the 3D estimation, the spatial relationship between the data and the associated values of elevation and roughness of the terrain is taken into account; with the estimated results, a model of wind energy resources is developed, given by a 3D mesh where to each node is associated the values of K and C. Finally, a method of combinatory optimization is described to find the values of p and s such that the mesh model is feasible and optimal for the given data. [ABSTRACT FROM AUTHOR]

A controversial and a highly debated issue has been estimated the hydrogeological properties of aquifers at the system scale from the geoelectrical parameters that characterize them due to the lack of a theory that supports the existence of functional relationship between geoelectrical parameters and hydrogeological properties. Equations that support a theory that back up the existence of such relationships are developed in this paper. [ABSTRACT FROM AUTHOR]

To obtain the necessary quality in the lateritic ore that is processed at Comandante Ernesto Che Guevara nickel plant, it was designed an integrated system of mining exploitation. This system conceives a technology for the natural drying of the mineral which has important advantages, but it has restrictions that limit its efficient implementation. In this paper, we propose the modifications that make possible to mitigate the limitations of technology, from the systematization of previous results obtained in simulation, modeling, and optimization of natural drying. The proposed innovations, integrally implemented, will improve the planning, execution and control of the process and, therefore, improving the natural drying technology of the laterites. [ABSTRACT FROM AUTHOR]

To obtain the necessary quality in the lateritic ore that is processed at Comandante Ernesto Che Guevara nickel plant, it was designed an integrated system of mining exploitation. This system conceives a technology for the natural drying of the mineral which has important advantages, but it has restrictions that limit its efficient implementation. In this paper, we propose the modifications that make possible to mitigate the limitations of technology, from the systematization of previous results obtained in simulation, modeling, and optimization of natural drying. The proposed innovations, integrally implemented, will improve the planning, execution and control of the process and, therefore, improving the natural drying technology of the laterites. [ABSTRACT FROM AUTHOR]

A controversial and a highly debated issue has been estimated the hydrogeological properties of aquifers at the system scale from the geoelectrical parameters that characterize them due to the lack of a theory that supports the existence of functional relationship between geoelectrical parameters and hydrogeological properties. Equations that support a theory that back up the existence of such relationships are developed in this paper. [ABSTRACT FROM AUTHOR]

The welding of steel of low carbon content is a common practice in the nickel industry, where components with steels of these characteristics are manufactured. The objective of the paper was to establish the microstructural behavior of the AISI 1025 steel when it was welded with two types of electrodes (E 6010 and E 7018), the first one deposited as a mattress, and the second one to guarantee mechanical resistance; they were made in a 240 x 240 x 10 mm plate with simple bevel preparation. The microstructures obtained with the electrode E 6010 are of the ferrite type Widmanstátten, columnar ferrite and intergranular pearlite, with a hardness of 345 HV, while with the electrode E 7018 the microstructures are ferrite Widmanstátten, austenite and martensite, with hardness of 332 HV. The decrease in hardness in the latter case is associated with the thermal treatment of multipass annealing. [ABSTRACT FROM AUTHOR]

The objective of this paper is to elaborate a geological-geotechnical model in three dimensions for the Cenozoic section which is the shallowest of Pinar del Rio City. It is intended that the model obtained is used in future as an interpretative basis for geotechnical phenomena arising in the urban environment. The procedure fallowed can be easily applied to other worldwide studies, mainly in the areas that exist a big volume of geotechnical information. The procedure fallowed can be easily reproduced in other study cases worldwide, specifically counting on a wide volume of geotechnical information. Six Engineering Geological Types (EGT) are identified in the model, namely, Artificial fill, Vegetation layer, Marine alluvial coarse grained soil, Marine alluvial fine grained soil, Eluvial soil and Bed rock. The 3D geological-geotechnical model illustrates the spatial arrangement of the EGT above, and can contribute significantly at decision making in urban planning. [ABSTRACT FROM AUTHOR]

Crushing mathematical modeling using particles population balance method is a fundamental tool for process analysis, optimization and design. This paper deals with the evaluation of the fracture events and process in cone and rolls crushers. For that proposes, is taken as reference Whiten (1972) structural model modifying fragmentation distribution function. This function was replaced by Austin and Luckie (1972) expression. For model development, was created an algorithm using Matlab 13a like determining resource of fractures parameters. Model estimated error for evaluated crushers established the viability of its use for modelling and simulation, particularly for rolls crushers that even before were simulated by simple fragmentation models. Classification and fragmentation distribution functions obtained, describe the events and process fracture essentials that take place in both crushers. [ABSTRACT FROM AUTHOR]

It is paper has as objective to characterize microstructures the aluminium alloys that are used in the production of cases for slings and obtained by foundry processes. After having lathed and the resistance among the two elements (case-sling) they were pressed with the employment of prints. The magnetic noise Barkhausen allowed to determining the effect of the compression on the cable according to the alloy type. The obtained microstructure is characterized by the size of the grain and their morphology by an orientation of the phase alpha in the alloy Al-Si-Mg, structures dendrites with silicon very fine eutectic in the alloy Al-Si-Cu and it structures polyhydric or acicular for the alloy Al-Si-Mg, this behaviour and a hardness of 224.8 HV, allow to settle down that the alloy of Al-Mg presents better properties to be subjected to compression process. [ABSTRACT FROM AUTHOR]

The objective of the present paper is to model the behavior of the compressive and thermal surface stresses originated in the wheel of the rotary dryer with the aim of carrying out fatigue and superficial wear tests on the wheels. Firstly, a theoretical model to estimate the surface stresses that originate in the wheel was established. An equivalent geometrical model of the wheel and the contact zone was discretized using ANSYS v.12.1. Lastly, simulations were carried out using the finite element method in order to determine the behavior of the contact stresses. The results showed that the maximum stress acts along the middle of the contact strip and its magnitude increases proportionally with the force on the wheel and its temperature. The highest value of maximum contact stress (415,14 MPa) was observed when the force acting on the wheel was 1 254 467 N and its temperature 100 °C, whereas the smallest value (87,662 MPa) was obtained for 1 153 915 N and 40 °C [ABSTRACT FROM AUTHOR]

This paper deals with the characterization of boride layers formed on the 316 stainless steel AISI type. A superficial treatment was applied through the method of boronizing with solid powder. The characterization of the microstructure was achieved by observing the boride layer and measuring thicknesses using optical microscopy, scanning, EDX and XRD techniques and calculating the superficial micro-hardness based on process parameters. With the results it was possible to evaluate the influence of technological variables on the microstructure of the treated area as well as on the superficial properties in terms of micro-hardness. The analysis of the test results indicates an improvement in the mechanical properties of the superficially modified material. [ABSTRACT FROM AUTHOR]

In this paper, we report several examples of Simpson's paradox in resource evaluation of Cuban lateritic deposits and discuss effects and boundary conditions of the Simpson's reversal. [ABSTRACT FROM AUTHOR]

This paper presents a wavelet-based two-stage progressive compression scheme to compress digital elevation models. This two-stage approach uses the best of two worlds: it uses a high performance and low complexity wavelet-based coding techniques for lossy compression as first stage; during the second stage the reconstructed model is subtracted from the original digital elevation model in order to obtain residuals which later are uniformly quantized and encode without loss to ensure the maximun height error in each point. [ABSTRACT FROM AUTHOR]

This paper summarizes more than three decades of investigation in relation to existing quaternary marine deposits in Cuba. These studies have revealed the existence of some quaternary lithostratigraphic units which are exclusive of the marine environment (Alegrías, Cayo Romano and Cayo Guillermo) and important to improve the Quaternary stratigraphy of Cuba. Some lithostratigraphic units of marine origin exposed in firm ground are missing as their deposits should have been removed as a result of marine transgressions and regressions. In nearly all the 5000 cays of the marine platform, there are unnominated Holocene deposits of marine and paludal environments. The marine platform bottom is partially covered by unnominated Holocene deposits of different granularity and composition, mainly overlaying the Jaimanitas formation. Sedimentation is calcareous in the morphogenetic external zone of the marine platform, with scarce accumulation of sand and vigorous coral growth. The morphogenetic internal zone is dominated by calcareous and calcareous-terrigenous muds and clay. The sectors with no marine platforms are dominated by an outcrop of Jaimanitas formation and Holocene bioclastic breccias. Only at the mouth of the rivers and in the bay there is accumulation of marine and terrigenous sediments with varying grain size. In general, the deposits are characterized by their small thickness and a granulometry and composition complex distribution; which is related to its origin, low input of sediments and the variation in hydrodynamic activity. [ABSTRACT FROM AUTHOR]

The difference in the solubility of amylxanthate copper complexes is the main factor of the flotation process for the recovery of dissolved copper ions, aspects in which it hasn't been researched enough. For this reason, it is presented the results of a research in this paper about the behavior of copper complexes as a function of aqueous average pH, evaluating the results from the specific contribution of both: the recovery and the kinetic of the flotation process, which is developed in a laboratory column flotation with potassium amylxanthate as a collector. The main operational variables of the column: liquid and gas superficial rate were constant as well as the initial foaming concentration. The transformation effects that take place in the system amylxanthate-copper-water are evaluated in the pH range from 4 to 13. The result shows an enhancement or increasing in the recovery of copper ions with the increment in the pH value to 11. It demonstrates the strong dependence between the copper recovery with the chemical characteristic of the system, an increment in the concentration of crystalline copper(I) amylxanthate has an increment in the floated copper, associated with this, it shows an increment in the retained gas fraction and in the bubble surface flow, which has direct effect in the kinetic of the flotation process. [ABSTRACT FROM AUTHOR]

In this paper we report a study about the behaviour of the copper amylxanthate complex by means of UV-Visible spectrophotometric technique in the pH range of 2-13 as well as a kinetic study of its formation showing the type of this process. A higher concentration of cupric amylxanthate was found in the range of pH 7 to 10. The Formation of carbon disulphide, in the pH values lower than 7 and higher than 10, shows decompositions of the amylxanthate ion diminishing the complex concentration. Kinetic study of the copper amylxanthate formation in the temperature range of 298-333 K shows that this process is controlled by a chemical reaction. It was also obtained the mathematical model for the kinetic process during the formation of cupric amylxanthate. Models reflect the behaviour of the studied parameters and their statistical significance. [ABSTRACT FROM AUTHOR]

The existence of the zeolite mineral, thomsonite, is reported for the first time in this paper. Thomsonite was found with other zeolites in veinlets that cut brown palagonite tuffs interbedded with green tuffs of Sabaneta Formation (Paleocen-Middle Eocen). The brown tuffs contain analcime and phillipsite and they appear mainly in Farallones locality at about 30 km to the Southwest part of Moa city. These tuffs may constitute a more basic composition member than the zeolitic green tuffs rich in clinoptilolite. The presence of high silica thomsonite of a moderate structural disorder was established, using X rays fluorescence analysis and X rays diffractions, a polarization microscopy and electron microprobe methods. Besides thomsonite, it was found analcime in the veinlets, possibly as a bedrock relic, and natrolite. [ABSTRACT FROM AUTHOR]

The present paper gives recommendations for developing researches oriented to improve prediction of solids concentration in sludge obtained by gravitational sedimentation. In thickener plant of PSA- Moa Nickel S.A. Company this prediction is studied by means of the historical, logical and passive experimentation methods. It is concluded that in order to solve the problem concerning the prediction of the solids concentration in sludge obtained by gravitational sedimentation, it is advisable to focus the research to the theoretical and empiric study of statistical correlation between this variable and the solids concentration obtained by others mechanical separation methods. [ABSTRACT FROM AUTHOR]

The main purpose of the present paper was to determine the multi-variable models to predict the Efficiency of Nickel reduction with greater effectiveness, when varying the chemical-mineralogical composition of lateritic ores in the Herreshoff furnaces. The research was made in a Loza (8 furnaces) of Punta Gorda Plant for working periods of 8 hours during three months. The data bases and their statistical processing were made in EXCEL. As a result, several multi-variable models were obtained , with effectiveness of prognosis superior than 95 %; the high effectiveness to predict the Efficiency of Nickel reduction was demonstrated when organizing the procedure of filtering Data Base by intervals of Limonite: Serpentine ratio (R5); it was confirmed the validity of the procedure of filtering Data Base to adjust the multi-variable models in the particular case of reduction roasting of lateritic ores, which can be employed to create an integrated software for its use in real time with the information in the INTRANET of Plant; it was explained the regularity in the signs and values behaviour of regression and correlation coefficients when comparing the best models of chemical and mineralogical Data Bases, with emphasis on the contradictions of the Ni variable, as well as the variables of Fe, Al and its minerals. [ABSTRACT FROM AUTHOR]

This paper has as main objective to establish a classification of the different types of movements of masses in slopes developed in the territory of Moa. The typology classification is based on the documentation of the movements found in the area, as well as characterization of all the geometric, structural elements and compositional of the material in which it has been developed; besides keeping in mind the classifications more accepted at international level. As a results a proposal is made of classification and description of the movements of masses containing the mechanisms of the slips in three main groups: mechanisms related with fall free of the rock, mechanisms of slips through a defined failure surface and mechanism of movements of masses in a disorganized way. [ABSTRACT FROM AUTHOR]

In this paper are shown the results of utilisation of the Differential Thermal Analysis technique (ATD), in the non- isothermal kinetic investigation of thermal decomposition of industrial basic nickel carbonate purified (free of sulphates) in 513- 633 K interval of temperatures, that excludes the water of hydration eliminated at lowest temperatures. Attention is dedicated to the possibility to use the Kissinger generalisated equation and the application of classical Kissinger method for the determination of kinetic parameters and the limitations of both methods. Also it is determinate the kinetic model for this step of the transformation and are compared the results with others reported previously by the authors. [ABSTRACT FROM AUTHOR]

A wide and detailed review of specialized papers about methods and diagnose index used to soil erosion assessment was done. It was evident the variety of existent methods that allow researchers to select between all of them, those that better satisfy their aims and data availability. Methods based on erosion landform mapping, evaluation and thematic mapping of factors that influence on erosion, field observations, radioactive isotopes, and modeling are described, being remarkable the importance of Geographic Information Systems (GISs) for developing some of them. The exposed methods are classified in qualitative and quantitative taking into consideration the result type they offer. The methods and diagnose index used to soil erosion assessment in Cuba during the last decades was reviewed. [ABSTRACT FROM AUTHOR]

Continuos regimes productions, as nickel production, require the stable operation of electric power systems (eps) against faults, so it is necessary, in order to avoid the prolongation of damage in all the eps, the installation of the protective system that can operate as fast as possible disconnecting the area of the eps faulted. the wrong operation of the protective systems may increment the cost of the industry production and in order to achieve to correct function of them, adequate tools as digitals simulators, are needed. this paper deals with modeling and simulation of protective relays used in the power transformers of two nickel industry. using a virtual library it is analyzed the performance of the protective system install in the industries, detecting deficiency and offering adequated solutions to avoid the increment of maintenance cost, sudden disconnection and wrong operation. using the protective virtual library created in matlab/simulink it is possible to predict wrong operations of the protective systems and offer solutions. [ABSTRACT FROM AUTHOR]

Very often the complexity and variability of a mineral deposit makes difficult to define homogeneous geologic domains that can be used to apply geological control to the estimation of the most important parameters. The fact, that it is not possible to create a geologic model with very well defined units, leads to work with a complex population and considerably downgrades the estimation quality. The cement raw material deposit Pastelillo is a typical case study where it is difficult to reproduce the geometry of the different technological types using the traditional method of geologic correlation. The different lithologies forming the deposits are mixed up as much in the plane as for the vertical direction. These frequent facial changes cause a great lithological and technological variability in the deposit. Considering this fact, it is proposed to use an interpolation method that allows estimating in the presence of complex populations. This paper focuses on the solution to the problem of establishing a technological and resources model of Pastelillo deposit, which involves the use of nonlinear geostatistical estimation technique: the indicator kriging. [ABSTRACT FROM AUTHOR]

The investigation was made in a Loza (8 furnaces) of Punta Gorda Plant for turns of 8 hours during three months The purpose of the paper was to determine the multi-variable models to predict the Efficiency of Nickel reduction with greater effectiveness, when varying the chemistry-mineralogical composition of lateritic ore in the Herreshoff furnace, which constitutes the base for the advanced control of the technological circuit: Mine-Ore Preparation Plant- Reduction furnaces Plant, with the purpose of elevating the productivity, reducing energy consumption and diminishing the production costs. The data bases and their statistical processing were made in EXCEL. As a result, several multi-variable models were obtained , with effectiveness of prognosis superior than 91 %; the efficacy of COMPRAC Software was validated to obtain models based on the mineralogical composition; the utility of the diagnosis method was demonstrated to detect the causes of subjective errors and to select the reliable information in the evaluated technological circuit; An efficient research methodology for the empirical modeling on scale of Demonstrative Production Unit was validated , based in the securing of the technical-operative Similarity of great Plants with continuous regime of operating. [ABSTRACT FROM AUTHOR]

In this paper is developed a methodology to carry out an energetic diagnostic in a given area of a production process. The methodology is particularly applied to the milling section in an ore improvement plant and it allows to reveals the main factors influencing in the unstable behavior of the specific energy consumption in that section. Regulation of feed to the ball mill, states to be the main factor to be controlled in order to reduce the specific energy consumption in 16 % respect the actual media. It is shown the feasibility to get this reduction, so that can be achieved an important profit when the section moves to a more rational use of electric energy. [ABSTRACT FROM AUTHOR]

The precipitation of Ni and Co mixes sulphides is one of the stages of the ammoniacal technological process in the cuban nickel industry, but the oxidation of sulphides disturbs its storage and transportation. This paper exposes results from chemical characterization by X-ray diffraction and mineragraphic analysis of mixed sulphides as well as from the kinetic investigation of the thermal oxidation of samples in isothermal and no isothermal regime. It's determined de most probable model and kinetic parameters of the physical-chemical transformations that occurs in oxidation process. It's concluded that oxidation of mixed sulphide concentrate follows 4 stages: lost of water and ammonio, degradation of superior sulphides, formation of sulphates and degradation of sulphates into oxides. Degradation of sulphides into oxides degradation of sulphides to oxides Nickel and cobalt sulphides obtained through leaching technology carbonates ammoniacal of laterític ferrous nickelitic ore is characterized and is studied in the kinetics of oxidation concentrated in nickel and cobalt sulphides applying the isothermic and not isothermic methods, being determined the most probable pattern and the kinetic parameters of the physical chemical transformations that take place in the process of oxidation. [ABSTRACT FROM AUTHOR]

The paper represents a hydrogeologic regionalization of Pinar del Río province in GIS platform. The principles of elaboration of this map propose the division of the territory starting from the automatic integration of a group of such natural variables as: physical-geographical characteristics, hydrology, geomorphology, hydrogeology and structure particularities. It is recognized the regional regularities and the common features of each hydrogeologic structure, such as: the sources of the underground waters, the recharge conditions, circulation and discharges of the horizons and aquifer complexes, hydrochemical and hydrodynamic zoning. [ABSTRACT FROM AUTHOR]

In this paper a quantitative physical characterization of the chromite concentrated with refractory characteristic belonging to the deposit Merceditas is presented, using for it technicals of infrared and Mössbauer spectroscopies, X-ray difractometry, chemical and grain size analysis. It settles down that the concentrate is constituted by the phases mineralogical well-known as chromopicotite, antigorite and chlorite, being determined its respective cristalo-chemical formula. By means of the techniques of thermal analysis (DTA, TG and DTG) the thermal behavior of a mixture of chromite concentrated and aluminum is studied with the purpose to valuing the possibilities of the products of the reduction like component of saturating mixtures for the thermodifusives surfaces of chromium and silicon in steels. [ABSTRACT FROM AUTHOR]

The potential field inverse problems are difficult to solve by means of automatic methods, one major reason for this is the inability of conventional procedures to locate the globally optimal set of parameters. This paper establish clearly the nature of the multiple optima problem for the research to inversion of potential field data in the six parameters model and investigates the consistency with three global optimization methods. The Multistart Simplex (MSX) method, a Genetic algorithm combined with Simplex (GSX) and the Shuffled Complex Evolution (SCE) method. All of them are able to find the optimal parameters set during the inversion of potential field data for a six-parameter model. In 100 independent trials of each algorithm the SCE procedure appears to be about 3 times more efficient than MSX procedure and twice time more efficient than GSX. The GSX procedure appears to be about 2 times more efficient than MSX. [ABSTRACT FROM AUTHOR]

In the smelting-workshop of the Mechanical Company of Nickel, Moa city, Holguín province, the creation and control of norms of materials consumption in the production of pieces is made of manual form, being a process slow and, sometimes, unreliable. This paper shows software that systematizes economic-technical information of the smelting that is very useful in the decision making from a scientific and technician analysis. The design and development of software are based on the use of the methodologies of analysis and structured design of computer science systems and the object-oriented programming by means of the tools of programming of Borland Delphi version 5.0. It can be used in smelting-workshops dedicated to produce and to repair pieces for the mechanical industry in Cuba. [ABSTRACT FROM AUTHOR]

The exploitation of sand and cruhed stone deposit, establish special problem for the characteristic of the natural environment where it is done. The prejudice for protecting the environment, joined to the legislation does that the mining activity should be done with a rational project that observe previosly the recovering of the affected ground according with the existing ecosystems. This paper presents an evaluation of the environmental impact that carries out the exploitation of fluvial deposit with sand and crushed stone, located into the limits of Alejandro de Humboldt park, both and the prevent measurement that will have to adopt themselves for minimizing the impact over the environment in order to resemble the exploitation and the protection of natural environment. [ABSTRACT FROM AUTHOR]

The synthesis of the Catalogue of Perceptible Earthquakes from 1528 to 1990, which have been obtained and elaborated to be used at the same time as a Data Base in a PC, is presented. Although usually, the periods of time which are used in seismic analysis are limited due to the lack of instrumental information, this Catalogue contain the enough amount of information to allow the extension of that periods of time. As a complement of the Catalogue, examples from the Atlas of Isoseismal Maps of Perceptible Earthquakes which epicenter located in Cuba, was also finished. The last one is fundamental for the characterization of Seismic Attenuation in Cuba in terms of intensity, for Seismic Hazard assessment. The temporal-spatial analysis of the perceptible earthquakes permit us to evaluate the Seismogenic Zones from the Seismotectonic point of view. Furthermore a theoretic-experimental analysis of the Attenuation's Law of Seismic Intensity from Greater Antilles, and the main parameters associated to Seismogenic Zones of Cuba, is showed. These ones were obtained from Isoseismal Maps of perceptible and large earthquakes. The results obtained from the probabilistic and deterministic Seismic Hazard Assessment, for different regions all over the country, have been unified in this paper. From the Seismic Hazard Map resulting, the Seismic Zonation Map with Engineering Purposes was also obtained; the last one was proposed for the New Seismic Cuban Design Code. As a contribution to the characterization of Cuban Seismicity an spatial -- temporary -- energetic analysis of the perceptible aftershocks was made, including their relation with our Seismogenic Zones, obtaining an empirical relationship between the Length of Rupture and the Magnitude values, estimated by Macroseismic Data. [ABSTRACT FROM AUTHOR]

Mineral deposit descriptive models are valuable geological information network usefull to explore and assessment the territories with these atributes in their geologic pattern and makes them perspectives for the discovery of new mineral resources. In this paper a generalized approach is given about weathering as main process in the formation of laterites as well as three proposal of Fe-Ni-Co laterite descriptive models developed on Mayarí-Baracoa Ophiolitic Belt located in Eastern Cuba. [ABSTRACT FROM AUTHOR]

The lateritic weathering crusts of the northeast of Cuba constitute sources of obtaining Ni. The relationship of this metal with the mineral phases of iron (goethite specifically) in the oxidized ores of the nickeliferous crusts has been revealed by diverse investigations ground in chemical and mineralogical analyses. In this paper they are conjugated, for profiles of different maturity degree, chemical, mineralogical and physical aspects at the level of profile, horizons and grain-sized class. The results showed a natural tendency of concentration of the different mineral phases towards certain grain-sized class. In the Moa deposit, as much in mature profiles as immature, goethite is concentrated in the grain- sized class smaller than 0,045 mm, which represents around 50 % in weight of the ochreous horizons for both types of profile, and contains 1,4 % of Ni. [ABSTRACT FROM AUTHOR]

In this paper it is exposed the obtention of concentrating of the zeolitic phases by means of centrifuge with heavy liquids starting from the zeolitic cryptocrystalline rock. By means of the results of the chemical analysis of the zeolitic concentrated and the x-ray diffraction, the crystalochemical formulas of zeolitic mineral of Tasajera deposit rocks are determined, as well as their solid product (seudofaujasite), obtained from the hydrothermal basic reaction the concentrated was subject of. An assessment of the ionic exchange capacities of the zeolitic mineral and of its hydrothermal solid product is made, being based on the crystallochemical formulas and on the experimental results. Lastly, the hydrothermal reaction is formulated and by means of it is determined experimentally the efficiency of this hydrothermal process experimentally. [ABSTRACT FROM AUTHOR]

In the present paper is done a critical analysis about the most conventional models that describe consumed energy-size reduction relationship, their principals limitations for the consumed energy evaluation in multicomponent grinding and the state for art of this thematic. Someone adequacies are done upon the Tijonov's model, that derive towards a new model for the consumed energy evaluation in the multicomponent grinding. Proposed model allows the consumed energy determination for each component in the mineral mixture, and the energetic flows of size classes from each component in the mixture. [ABSTRACT FROM AUTHOR]

The experimental scale as a topic is approached in this paper with the objective of evaluating the behavior of the recovery of Ni and Co in the ammoniacal-carbonate technology and in a test bank for the reduction roasting and leaching. This test bank was built by a company that needs to carry out these tests periodically. In the present work it have been analyzed the most frequent errors made while carrying out this kind of research. The analysis has been made by means of the study of a real case. During the analysis it was recommended to consider the convenience of building a multi-purpose installation for the company, at mini-plant scale of continuous and transportable work in order to diminish the costs of any type of research, including any type of technological innovation in the roasting-leaching technological circuit. Besides this installation will make easier the technological evaluation, in a more reliable way, of other useful components present in the laterite with lower contents in comparison with the one of Co. [ABSTRACT FROM AUTHOR]

This paper presents the reactions of precipitation of cobalt (III) oxide, substance which is employed in the nickel industry and the purification of the industrial liquors. For doing this research the air is employed as oxidant agent, regulating environmental pH with hydroxide of sodium, carbonate of sodium and the mixture of both, doing the thermodynamic analysis for determining its spontaneity in the interval of temperatures from 303 to 353 K. The values were calculated in the variation of free energy and the constants of equilibrium to the given, according to the method proposed by Criss and Cobble. In each proposed reactions are studied the behavior of pH is the course of time and it is determined the percentage of the product submission obtained. The percentage of total cobalt in form cobalt (III) are determine. Those solids were characterized by diffraction of X rays. From the studied reactions only is possible to reach the derived product in that one that is used hydroxide of sodium as basic reagent (reaction I), obtaining a percentage of submission higher than 93 %. [ABSTRACT FROM AUTHOR]

This paper is intended to show a new software "MECCA" to obtain synthetic traces from acoustic well logs, as well as some experiences in using these techniques in geological studies. Some results are shown, obtained by using the above mentioned soft ware with acoustic well log data from Rabihorcado well in Guacanayabo Gulf, in order to do the lithostratigraphic referencing of seismic reflections. [ABSTRACT FROM AUTHOR]

In this paper the methodology for calculating of useful life time of cylindrical founding core during its permanence in outdoor moisture, in the time intervals from instant in which they are made to laundry moment, is described. The problem of calculation the limiting time was solved by the moisture diffusion process analysis in these media. The functional dependence of limiting time with both radial dimensions of cylindrical core and the effective diffusion coefficient of the atmospheric water in the mixture, that was used for conforming the core, was found. The dependence of limiting time with both the percent increase in the equilibrium humid mass, the percent increase in the critical humid mass and the environmental moisture was found too. [ABSTRACT FROM AUTHOR]

In this paper are explained the basics principles to keep in mind upon defining any procedure in order to determine a rational mesh to obtain samples, in order to carry out the exploration of the laterite deposits from Cuba. These principles part from the characteristics of the parameters that are studied (in particular the variability), the unit between the level of the knowledge to we are aspired, and the model that is employed in order to represent and study the behavior of these parameters. The necessity of modeling panels on supports of ó blocks is accentuated instead of making it on punctual supports as well as the convenience of using regular mesh. [ABSTRACT FROM AUTHOR]

This paper shows a valuation of different methodologies used to calculate the Transfer Coefficients (Kt) of alloy elements during the metallurgist process of Submerged Arc Welding taking in account the contribution of alloy elements starting from flux and from the wire-electrode. It is experimentally determined the chromium and manganese Kt in ceramic and commercial HF-600 flux. [ABSTRACT FROM AUTHOR]