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1 – 10 of 796Fuchuan Huang, Fukang Deng, Kang-Chun Li and Ke Qin
Aiming at the high temperature, high speed, high precision and high surface quality of the copper belt cold rolling, the purpose of this paper is to develop a new type of…
Abstract
Purpose
Aiming at the high temperature, high speed, high precision and high surface quality of the copper belt cold rolling, the purpose of this paper is to develop a new type of lubricant for cold rolled copper belt.
Design/methodology/approach
The component of the developed oil was determined based on the physical and chemical properties of the base oil and the tribological properties, the oxidation resistance properties, the rust resistance properties, the anti-foam properties, the demulsibility and the other properties of the additives. The orthogonal experiment method was used to determine the optimum adding amount of the additives; finally, the developed oil formulation was determined.
Findings
The physical and chemical experiment results show that the developed oil has a good performance of oil film bearing capacity and oxidation resistance. The simulation of rolling experiment found that the developed oil can significantly reduce rolling pressure and effectively reduce the friction in the process of rolling.
Originality/value
The experimental results show that the developed oil has excellent performance and can meet the requirement of lubrication in the process of cold rolling copper belt.
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Abstract
Alagtaihert Al lies in the marginal areas of Altai which belongs to Mongolia. Mineral resources are rich, especially copper, and the degree of exploration is poor in this area. Based on the investigation and analysis about regional strata, geological structure and previous researches, it is considered that magma activity supplied sources of copper deposits and tectonic movement accelerated mineral dressing. Through electrical geophysical detection, it is indicated that the strike of copper belt is NNW, zonal distribution and sectional concentration are the characteristics about copper deposits. Combined geological and geophysical properties to present the metallogenic mechanics and model: Metal mineral crystallization was formed with metasomatism happened in hydrothermal process; the type of hydrothermal copper belt was formed far away from the rock after the period of pegmatite and gas-hydrothermal; the depth of copper deposits is about 300m and most of them were collected from 22 to 150m.
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Chester Street, Aston, Birmingham, 6. The ‘Donald’ Patent Barrel Lifter Truck and Stand, the three‐in‐one appliance. Barrels up to 7 cwts. lifted and transported by one man…
Abstract
Chester Street, Aston, Birmingham, 6. The ‘Donald’ Patent Barrel Lifter Truck and Stand, the three‐in‐one appliance. Barrels up to 7 cwts. lifted and transported by one man. ‘Donald’ Patent Barrel Lifter Stands for Oil Stores.
Copper market outlook.
Details
DOI: 10.1108/OXAN-DB230271
ISSN: 2633-304X
Keywords
Geographic
Topical
Hao Wu, Xiangrong Xu, Jinbao Chu, Li Duan and Paul Siebert
The traditional methods have difficulty to inspection various types of copper strips defects as inclusions, pits and delamination defects under uneven illumination. Therefore…
Abstract
Purpose
The traditional methods have difficulty to inspection various types of copper strips defects as inclusions, pits and delamination defects under uneven illumination. Therefore, this paper aims to propose an optimal real Gabor filter model for inspection; however, improper selection of Gabor parameters will cause the boundary between the defect and the background image to be not very clear. This will make the defect and the background cannot be completely separated.
Design/methodology/approach
The authors proposed an optimal Real Gabor filter model for inspection of copper surface defects under uneven illumination. This proposed method only requires a single filter by calculating the specific convolution energy of the Gabor filter with the image. The Real Gabor filter’s parameter is optimized by particle swarm optimization (PSO), which objective fitness function is maximization of the Gabor filter’s energy average divided by the energy standard deviation, the objective makes a distinction between the defect and normal area.
Findings
The authors have verified the effect with different iterations of parameter optimization using PSO, the effects with different control constant of energy and neighborhood window size of real Gabor filter, the experimental results on a number of metal surface have shown the proposed method achieved a well performance in defect recognition of metal surface.
Originality/value
The authors propose a defect detection method based on particle swarm optimization for single Gabor filter parameters optimization. This proposed method only requires a single filter and finds the best parameters of the Gabor filter. By calculating the specific convolution energy of the Gabor filter and the image, to obtain the best Gabor filter parameters and to highlight the defects, the particle swarm optimization algorithm’s fitness objective function is maximize the Gabor filter's average energy divided by the energy standard deviation.
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Hamid Ashraf and Frederick Cawood
The fundamental purpose of this research is to compare Pakistan’s mineral policy instrument with that of leading developing minerals-based economies and to highlight the gaps…
Abstract
Purpose
The fundamental purpose of this research is to compare Pakistan’s mineral policy instrument with that of leading developing minerals-based economies and to highlight the gaps. Mineral resources development can act as an engine for country growth and have the potential to transform economies and societies. The extent to which such transformation takes place varies depending upon the method of their use.
Design/methodology/approach
This paper conducts a gap analysis between Pakistan and leading developing minerals-based economies to identify key policy gaps. Two basic principles were kept in mind with the choice of countries: first, only developing countries were considered and, second, at least two countries had to be Islamic. Eight developing countries Chile, Mexico, Brazil, Peru, India, South Africa, Kazakhstan and Turkey were selected.
Findings
The most important finding of the exercise is that Pakistan’s mineral sector is lacking an enabling institutional, fiscal and regulatory framework for the optimal development of its mineral resources.
Practical implication
Pakistan’s mineral resources have the potential to expand its economy and benefit its citizens. For this to happen, Pakistan must first establish what beneficiation is realistically expected from its mineral resources and, second, formulate a mineral policy based on leading practices to attract mining investment and aim for a sector contribution to gross domestic product of 5 per cent.
Originality/value
This paper presents original work on how Pakistan should formulate its mineral policy to extract maximum benefit from its mineral resources.
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Óscar Carpintero, Ivan Murray and José Bellver
The aim of this paper is to analyse the recent changes in the role played by Africa as a traditional natural resources supplier for the world economy in a multipolar context. We…
Abstract
The aim of this paper is to analyse the recent changes in the role played by Africa as a traditional natural resources supplier for the world economy in a multipolar context. We highlight, on the one hand, how Africa remains a prominent supplier of critical minerals needed for information and communication technologies (ICT), including platinum, vanadium, coltan, chromium, manganese, zirconium, etc., and how the boomerang effect results in Africa also importing electronic waste. On the other hand, we show how the BRICS’ growth model, based on a very intensive use of natural resources acquired through international trade, is now being fuelled by Africa too. BRICS countries (especially China and India) are making foreign direct investments in Africa using their state companies to ensure the supply of natural resources under favourable economic terms. Thus, Africa appears as a disputed territory between the old domination of the advanced capitalist countries and emerging powers like the BRICS. However, this should not mask the fact that the European Union and North America are still the dominant foreign powers in the continent. Finally, we discuss which scenarios are open to further this multipolar moment, particularly in the wake of the great crisis.
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Public universities in eastern and southern Africa have for a long time depended largely on grants from national governments for most of their recurrent and capital budgets…
Abstract
Public universities in eastern and southern Africa have for a long time depended largely on grants from national governments for most of their recurrent and capital budgets. Statutes of various universities also allow them to get external aid and donations mainly for capital developments, technical assistance and staff training. In the last decade, there has been pressure on public universities in the region to cut back on their budgets as a result of declining government grants occasioned largely by political and economic structural changes. Universities are responding by putting in place a wide range of programmes to generate their own income to augment the dwindling allocation from national governments. This paper discusses current developments within universities in eastern and southern Africa in an environment of rapid technological developments.
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Impact of falling commodity prices and dearth of capital on the resource sector.
Details
DOI: 10.1108/OXAN-DB205962
ISSN: 2633-304X
Keywords
Geographic
Topical
Presidential politics in the Democratic Republic of Congo.