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Heavy metals play a crucial role in the economic development of any nation. Industries utilizing heavy metals, consequently, emanate a large volume of metal-containing liquid effluents. Since metals are non-renewable and finite resources, their judicious and sustainable use is the key. Hazardous metal-laden water poses threat to human health and ecology. Apart from metals, these industrial effluents also consist of toxic chemicals. Conventional physical–chemical techniques are not efficient enough as it consumes energy and are, therefore, not cost effective.

It is known that biomaterials namely microorganisms, plants, and agricultural biomass have the competence to bind metals, in some cases, selectively, from aqueous medium. This phenomenon is termed as “metal biosorption.” Biosorption has immense potential of becoming an effective alternative over conventional methods. The authors in the present chapter have used secondary data from their previous research work and attempted to develop few strategic models through their feasibility studies for metal sustainability.

The main aim of this study was to improve current efficiency and to obtain thicker coatings via aluminum oxide (Al₂O₃) addition to the chromium (Cr) (III) bath.

Pure Cr and nanocomposite Cr–Al₂O₃ coatings were electrodeposited from Cr (III) bath onto cathode copper substrates by conventional method. Dependence of current efficiency to current density, Al₂O₃ content and particle size were investigated.

Current efficiency increased with Al₂O₃ amount and decreased with Al₂O₃ particle size. Maximum current efficiency was achieved at 25 A/dm₂ for pure Cr and 30 A/dm₂ for composite coatings. Al₂O₃ bath content, current density and stirring rate increased the coating Al₂O₃ weight per cent significantly. Addition of Al3+ bath composition inhibited nanoparticle agglomeration, increasing film homogeneity. Cr–Al₂O₃ nanocomposites showed higher microhardness and better corrosion resistance than pure Cr layer.

Cr (III) is not as toxic and as carcinogenic as Cr (VI) which is widely used for Cr electroplating these days. Low current efficiency and poor product quality are, however, major drawbacks of the former. This paper describes significant improvements obtainable by addition of Al₂O₃ nanoparticles to the Cr (III) bath for increasing the microhardness, the corrosion resistance and the current efficiency of the deposition.

Water is a basic human need, a finite life support system and a key to prosperity. Unplanned industrialisation, urbanisation and impact of liberalised import of wastes intended for recycling have negatively affected the water environments in India. This is further exaggerated by lack of discipline and a weak obligation towards conservation and pollution prevention. Measures have to be especially taken to resolve the groundwater problems. While groundwater resources are quite well assessed, overexploitation still occurs frequently. There has been a considerable lack in implementing existing policies as well as developing new laws and policies. To mitigate the problems, co‐operation needs to be mobilised at all levels of the federal set up with the stakeholders and the people at the lowest appropriate level concerning planning and decision making. Water must be considered as a national asset and a basic human right to be provided to citizens in proper quantity and safe quality with equity and fairness amongst the users.

This paper aims to explore a framework for implementing Lean Construction (LC) to provide corrective actions for quality defects, customer dissatisfaction and value creation during the construction of megaprojects.

This paper presents a case study involving the construction of the Mohamed VI Tower in Morocco. It is the tallest tower in Africa, with 55 floors and a total height of 250 m. This study of the quality of the work and the involvement of the LC was carried out using the Define–Measure–Analysis–Improve–Control approach from Lean six sigma. It describes the Critical to Quality and analyses the root causes of quality defects, customer dissatisfaction and variation in the quality process.

Firstly, the results of this study map the causal factors of lack of quality as established in the literature. Secondly, the LC tools have reduced non-value-added sources of quality waste and, consequently, improved critical quality indicators.

This document focuses on one part of the tower’s construction and is limited to a project case in a country where LC is rarely used.

This study reinforces the literature reviews, surveys and the small number of case studies that have validated the potential of LC and further clarifies future directions for the practical emergence of this quality improvement approach, especially for large-scale projects.

Modeling represents the art of translating problems from an application area into tractable mathematical formulations whose theoretical and numerical analysis provides insight, answers and guidance useful for the originating application. The purpose of this paper is to determine the causal causes of schedule overrun and cost escalation of highway projects in Egypt in order to be used as independents variables in mathematical models for predicting the percentages of schedule overrun and cost escalation of such projects in Egypt.

A survey of a randomly selected samples yielded responses from 40 owners, 15 consultants and 56 contractors. The survey includes 38 schedule overrun factors and 26 cost escalation factors. The effectiveness degree of the identified factors has been identified by the triangle fuzzy approach.

The results of the survey show that “contractor’s technical staff is insufficient and ineligible to accomplish the project” is the most important cause of schedule overrun, while the major cause of cost escalation is inadequate preparation of the project concerning planning and execution.

The main contribution of this study is predicting the percentages of schedule overrun and cost escalation of highway projects in Egypt. Through the application of the linear regression analysis method and statistical fuzzy theory, four predictive models have been developed and it has been noted that the linear regression-based model shows prediction accuracy better than statistical fuzzy-based model in predicting percentages of schedule overrun and cost escalation.

The purpose of this paper is to investigate the feasibility of solving turbulent flows based on smoothed finite element method (S-FEM). Then, the differences between S-FEM and finite element method (FEM) in dealing with turbulent flows are compared.

The stabilization scheme, the streamline-upwind/Petrov-Galerkin stabilization is coupled with stabilized pressure gradient projection in the fractional step framework. The Reynolds-averaged Navier-Stokes equations with standard k-epsilon model are selected to solve turbulent flows based on S-FEM and FEM. Standard wall functions are applied to predict boundary layer profiles.

This paper explores a completely new application of S-FEM on turbulent flows. The adopted stabilization scheme presents a good performance on stabilizing the flows, especially for very high Reynolds numbers flows. An advantage of S-FEM is found in applying wall functions comparing with FEM. The differences between S-FEM and FEM have been investigated.

The research in this work is limited to the two-dimensional incompressible turbulent flow.

The verification and validation of a new combination are conducted by several numerical examples. The new combination could be used to deal with more complicated turbulent flows.

The applications of the new combination to study basic and complex turbulent flow are also presented, which demonstrates its potential to solve more turbulent flows in nature and engineering.

This work carries out a great extension of S-FEM in simulations of fluid dynamics. The new combination is verified to be very effective in handling turbulent flows. The performances of S-FEM and FEM on turbulent flows were analyzed by several numerical examples. Superior results were found compared with existing results and experiments. Meanwhile, S-FEM has an advantage of accuracy in predicting boundary layer profile.

The effects of γ‐radiation on both the optical and the electrical properties of Tellurium dioxide (TeO₂) thin films were investigated. TeO₂ thin films were fabricated using thermal vacuum deposition method. Samples were exposed to a ⁶⁰Co γ‐radiation source with a dose rate of 6 Gy/min. Absorption spectra for TeO₂ thin films were recorded and values of the optical band gap for as‐deposited and γ‐irradiated films were calculated. Sets of measurements based on Hall effect were carried out. From the data received the dependences of sheet resistance, density of charge carriers, mobility and Hall coefficient with radiation dose were determined.