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Showing posts with the label ournal of mining and metallurgy

A note on the Burger’s method

Abstract The existence and uniqueness of the solutions to an infinite system of nonlinear equations arising in the  dynamic analysis of large deflection of a plate are discussed. Under the assumption that the rim of the plate is prevented from inplane motions, explicit equation for the coupling parameter is given. Keywords: Existence, uniqueness, Berger’s method.1991 Mathematics Subject Classification. 46(Functional analysis),73(Mechanics of solids) Introduction In the analysis of classical mechanics problems, there are cases where linear mathematical model can not fully describe the phenomena. If the deflection of the plate is of order of magnitude of its thickness, the differential equations for the deflection and displacements can be written in terms of nonlinear equations. These nonlinear equations are usually difficult to obtain the solution. Thus several attempts have been tried to obviate the difficulties. Among these attempts, it was Berger’s...

Existence and Uniqueness of the solution of large deflection of circular plate by the Burger’s method

Introduction In the analysis of classical mechanics problems, there are cases where linear mathematical model can not fully describe the phenomena. If the deflection of the plate is of order of magnitude of its thickness, the differential equations for the deflection and displacements can be written in terms of nonlinear equations. These nonlinear equations are usually difficult to obtain the solution. Thus, several attempts have been tried to obviate the difficulties. Among these attempts, it was Berger’s method which drew much attention. Berger[1] derived as implified nonlinear equations for a plate with large deflections by assuming that the strain energy due to the second invariants of the middle surface strains can be neglected when deriving the differential equations by energy method. Berger restricted his analysis to static and isotropic cases. Later, his procedure was generalized to dynamics of isotropic plates by Nash and Modeer [2] and to dynamic phenomena in anisotr...

Theoretical Feasibility Research on 3D Printing Technology Applied to Statics Model Experiment

  Abstract 3D printing is effective to manufacture experimental models widely used in analogous statics tests before practical engineering applications. Whereas, traditional statics model experiments with strict dimensionless function are hardly to be established through 3D printing items according to similarity theory. To find a solution, this paper theoretically simplifies the statics system based on reducing constrains of weight and Poisson’s ratio. This simplification is the core of a new method of additional weight and correction to identify the simplified and the original statics systems. Operation procedures are displayed through case studies using the new method. 3D printed materials for specific statics experiments are validated as well through coefficient corrections. The results will finally contribute to 3D printing technology applied to analogic static research, for not only academic but also industrial purposes.   Read more about this article : ht...

Corrosion Protection of Aluminium in Sulphur dioxide Environment by the use of Nanocoating and Electrospray Techniques

  Abstract Aluminium is a very useful metal. It is easily converted into suitable forms so it fits for in various appliances like households, industries, aerospace, electronic, transport and other processes. It is produced corroding affect in sulphur dioxide environment. Al interacts with sulphur dioxide in presence of humidity to produce corrosive medium for its. It creates acidic environment for Al metal and forms corrosion cell on its surface. The electrode potential difference occur between Al|Al3+ anode and cathode H+|H2 thus corrosion reaction takes place on the surface of base metal and produces different forms corrosion like galvanic, pitting, stress, crevice, intergrannular etc. The organic compound terahydro-dibenzo[a,d][7]annulene-5,11-dioxime and zinc oxide electrospray were used for corrosion protection of Al in sulphur dioxide environment. The terahydro-dibenzo[a,d] [7]annulene-5,11-dioxime and ZnO electrospray formed composite barrier on aluminium me...

Syngas Compositions, Cold Gas and Carbon Conversion Efficiencies for Different Coal Gasification Processes and all Coal Ranks

  Abstract This Paper presents comparison of syngas compositions, for all coal ranks, as produced from different types of coal gasification processes currently in use, namely entrained flow, fluidized bed, and fixed bed gasifiers. Cold gas and carbon conversion efficiencies were investigated. The syngas composition varies with the applied gasification process. The importance of this research arises from the fact that gasifiers produce the environmentally clean fuel required to run any Integrated Gasification Combined Cycle power system. A procedure was conducted to get estimates for bituminous coal. It is important to have knowledge of the chemical reactions which take place in each gasifier and the raw syngas produced from the specific reaction involved to develop an Integrated Coal Gasification Combined Power Generation plant with CO 2 recovery in order to increase the cycle efficiency and mitigate CO 2 emission and other pollutants. The results indicate that t...

Bioleaching of Basic Metals from Electronic Waste PCBs

  Abstract E-waste is an emerging problem that has to be attending worldwide. The best way for E-waste management is recycling. Bioleaching is a novel method to extract metals from E-waste. In this research, bioleaching of Cu and Ni from an E-waste sample was examined using acidophil microorganisms. Different kinds of E-waste were purchased; the sample size reduced to lower than 100 microns. Acidithiobacillus ferrooxidans was adapted to the 15 g/l of the E-waste sample. Eh, pH, bacterial count, and metal recovery were followed in a period of 25 days. By using inductively coupled plasma optical emission spectroscopy (ICP-OES) identified Cu and Ni were recovered respectively 99% on 11 th day and 98% on 14 th day. The results of field emission scanning electron microscope (FE-SEM), Fourier transform infrared spectrometer (FTIR), and X-ray diffraction before and after bioleaching emphasize the great efficiencyofbioleaching. Read more about this article :  https:...

Overview of Known Alkaliphilic Bacteria from Bauxite Residue

Abstract Alkaliphilic bacteria usually grow well at pH 9, and the most extremophilic strains can grow up to values as high as pH 12-13. This group of bacteria has the ability to metabolically reduce alkalinity and are tolerant of high concentrations of ions and metals. Interest in extreme alkaliphiles has been shown as they are sources of useful, stable enzymes, and the cells themselves can be used for biotechnological and other applications at high pH values. Many industrial processes produce highly alkaline waste that is contaminated with toxic trace metals/metalloid. Thus, using alkaliphilic microorganisms is considered an attractive alternative method for treating industrial alkaline residues. Bauxite refining is one of the activities that most produces highly alkaline waste. Alumina extraction from bauxite using concentrated sodium hydroxide in the Bayer process generates a slurry and an extremely alkaline (pH of 9 to 13) by-product known as bauxite residue or r...

The Use of Air Jigging to Recycle Construction and Demolition Waste

Abstract The recycling of Inert CDW in new concretes remains problematic. Only a part of this material can be used to substitute coarse aggregates in new concretes, mainly the liberated coarse aggregates from demolished concretes. This paper presents the processing of Inert CDW in air jigs aiming at concentrates with high concrete particle contents. The paper compares different studies carried out with laboratory air jigs aiming at a concentration of concrete particles, which can partially substitute coarse aggregates in new concretes. Introduction Nowadays, large quantities of CDW (Construction and Demolition Waste) are produced worldwide: European Union between 310 and 700 million tons [1], United States 145 million tons [2], China about 1 billion tons [3], etc. In Europe, this waste represents over 30% of all solid waste generated [1]. Current CDW processing plants only separate light materials (such as plastics, paper, wood, etc.) and metal parts (fe...

Acid and Metalliferous Drainage–A Global Environmental Issue

Abstract Acid and Metalliferous Drainage (AMD) is a critical environmental problem worldwide. It occurs when sulfide minerals, primarily pyrite, oxidise chemically or biologically to produce acidic wastewater containing elevated concentrations of sulfate and toxic elements. This short paper presents a very brief and general introduction of AMD, with a specific focus on two categories of AMD remediation options including source- and migration-control. Some most recent examples of potentially viable and economically sustainable surface passivation strategies for AMD control at-source are briefly discussed in this review.   Read more about this article : https://lupinepublishers.com/mining-mechanical-engineerning/fulltext/acid-and-metalliferous-drainage-a-global-environmental-issue.ID.000101.php Read more   Lupine Publishers Google Scholar   Articles : https://scholar.google.com/citations?view_op=view_citation&hl=en&user=dtO2BpUAAAAJ&citation_for_view...