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The purpose of this study is to focus on simulation of wire mesh demisters in multistage flash desalination (MSF) plants. The simulation is made by the use of computational fluid dynamics (CFD) software.

A steady state and two-dimensional (2D) model was developed to simulate the demister. The model employs an Eulerian-Eulerian approach to simulate the flow of water vapor and brine droplets in the demister. The computational domain included three zones, which are the vapor space above and below the demister and the demister. The demister zone was modeled as a tube bank arrange or as a porous media.

Sensitivity analysis of the model showed the main parameters that affect demister performance are the vapor velocity and the demister permeability. On the other hand, the analysis showed that the vapor temperature has no effect on the pressure drop across the demister.

The developed model was validated against previous literature data as well as real plant data. The analysis shows good agreement between model prediction and data.

This work is the first in the literature to simulate the MSF demister using CFD modeling. This work is part of a group effort to develop a comprehensive CFD simulation for the entire flashing stage of the MSF process, which would provide an extremely efficient and inexpensive design and simulation tool to the desalination community.

Improved nuclear reactor configurations that address major concerns of environmentalists and safety analysts are discussed. In addition to social acceptance, these new modes of power generation have economic potential to become the dominant producers of energy in the twenty‐first century. The class of power generation with this promise is the high temperature gas reactor (HTGR); the variant we focus on is the pebble‐bed modular reactor (PBMR). We also focus on using nuclear power as an energy source for desalinating seawater. Finally, the case is made that HTGR reactors are ideal for supplying the high‐temperature heat needed for manufacturing molecular hydrogen, a leading candidate for clean fuel consumption. These three themes are developed in a broad context with the objective of recommending policy actions dealing with global warming, public health, and economic opportunity.

New technology developed by CIBA‐GEIGY (UK), in collaboration with the United Kingdom Atomic Energy Authority, looks like providing a breakthrough in the control of scale in high temperature desalination plant. CIBA‐GEIGY are claiming that the product, based on a polymeric carboxylic acid, is effective with brine temperatures up to 250°F, has minimal handling, storage and corrosion problems and will reduce operating and capital costs on new high temperature plants. The company has designated the product Belgard EV and it is an extension of the recently introduced Belgard 800 range of water treatment chemicals.

The objective of this article is to propose the use of nuclear power to provide electricity and wide‐scale desalination to meet future population growth in Israel and a Palestinian State.

The extent of future water and power shortages in Israel and a Palestinian States expounded in the article and various methods for alleviating these shortages are explored. Comparisons are made with historical approaches.

Nuclear pebble‐bed technology is found to be the most cost‐effective way to energize future water and power needs. It is safe, non‐polluting, and terrorist resistant.

This article makes the case that abundant water and power in the Middle East is both a pre‐requisite and a stimulant for peace in the region.

The purpose of this study was to investigate the corrosion of rusted carbon steel in dilute NaCl solution, with the purpose of exploring the effect of the rust layer on metal corrosion and establishing a corrosion model for rusted iron.

The corrosion behavior of rusted carbon steel in dilute NaCl solution was studied by means of weight-loss determinations, scanning electron microscopy, Raman spectrometry and electrochemical techniques.

The results indicated that carbon steel had a similar corrosion behavior in all three NaCl solutions. The iron rust, which consisted of a thin γ-FeOOH layer and a thick Fe₃O₄ layer, can facilitate the corrosion process of carbon steel via reduction of γ-FeOOH and the large area cathode of Fe₃O₄. Hence, the corrosion rate of carbon steel was accelerated significantly and finally was determined by the limiting diffusion rate of oxygen.

A corrosion model of rusted carbon steel was established, suggesting that iron rust formed in all slightly acidic waters with low alkalinity probably promotes the corrosion of carbon steel. Anti-corrosion measures for iron in this type of solution, such as desalination water, should be aimed to reduce the promotional effect of the rust layer on metal corrosion.

This case study of the State of Qatar examines government educational policy and economic development in Qatar’s strategy to diversify its oil and gas-based economy into knowledge production. Qatar presents a particularly interesting case since its substantial investments in the past decade in education, Information and Communications Technologies (ICT), research and development (R&D), and coastal development and tourism are all highly intertwined both in practice and from a national policy perspective. Armed with billions of dollars of sovereign wealth funds (SWF) from its gas and oil industries, the government of Qatar has embarked on both domestic and overseas investment campaigns including education, sports, internet and telecommunications, healthcare, overseas land purchases (food security), cultural institutions and museums, increased desalinated water capacity, and coastal development and tourism projects. Education and research, most notably Qatar Foundation’s Education City, Qatar National Research Fund (QNRF), and the Qatar Science and Technology Park (QSTP), stand at the heart of Qatar’s investment in human development and long-term economic and social sustainability. Despite large outlays in knowledge economy initiatives, the country, however, is facing significant challenges in rapid population growth, reliance on expatriate labor for its skilled labor needs, an underdeveloped education system, and an undiversified economy which revolves around hydrocarbon rents.

The aim of this paper is to investigate the effect of cathodic charging and corrosion behavior of Ti‐48Al‐2Cr‐2Nb alloy in hydrochloric acid solutions.

TiAl alloy specimens of thickness 0.5 mm were cathodically charged in 0.1 M HCl solution at room temperature. The prominent current densities selected for this investigation were 25 and 50 mA cm⁻² for durations of 24‐120 h. The change in weight of the specimen after charging was measured by a microbalance with an accuracy of ±1 μg.

The nature of the specimen surfaces was characterized by X‐ray diffraction (XRD), auger electron spectroscopy (AES) and scanning electron microscopy (SEM) equipped with energy dispersive X‐ray spectroscopy (EDS). XRD revealed the phase transformation from microcrystalline to nano‐crystalline, particularly after high charging times (120 h) and high current density (50 mA cm⁻²). AES and EDS further assessed the compositional fluctuations on both cathodically charged and potentiodynamically polarized specimens. Surface corrosion leading to the generation of microcracks throughout the surface region was observed by SEM. Cathodic charging and the polarization process were responsible for embrittlement and pitting. Decreases in both weight and Vickers hardness values with an increase in charging time revealed that surface erosion depended strongly upon charging density.

The results presented in this work shed light on the role of alloying elements the passive behavior and their implications on their stability in hydrochloric acid environments.

Acute shortage of potable water and energy supplies is expected to raise in developing countries in the near future. One solid way to address these issues is to exploit renewable energy resources efficiently. Hence, this study aims to investigate wind and solar energy use in the coastal areas of southern Iran for renewable-powered seawater desalination and hydrogen production systems.

To accomplish the aforementioned purpose, five areas most prone to the problems in Iran, namely, Mahshahr, Jask and Chabahar ports and Kish and Hormoz islands were scrutinized. To ascertain the amount of wind and solar energy available in the areas, Weibull distribution function, Angstrom–Prescott equation and HOMER software were used.

The findings indicated that wind energy density in Kish was 2,014.86 (kWh/m².yr) and solar energy density in Jask equaled to 2,255.7 (kWh/m².yr) which possessed the best conditions among the areas under study. Moreover, three commercial wind turbines and three photovoltaic systems were examined for supplying energy needed by the water desalination and hydrogen production systems. The results showed that application of wind turbines with rated power of 660, 750 and 900 kWh in Kish could result in desalting 934,145, 1,263,339 and 2,000,450 (m³/yr) of seawater or producing 14,719, 20,896 and 31,521 (kg/yr) of hydrogen, respectively. Additionally, use of photovoltaic systems with efficiency of %14.4, %17.01 and %21.16 in Jask could desalinate 287, 444 and 464 (m³/yr) of seawater or generate 4.5, 7 and 7.3 (kg/yr) of hydrogen, respectively.

Compared to the huge extent of water shortage and environmental pollution, there has not been conducted enough studies to obtain broader view regarding use of renewable energies to solve these issues in Iran. Therefore, this study tries to close this gap and to give other developing nations the idea of water desalination and hydrogen production via renewable energies.

The purpose of this paper is to analyze differences between multichannel and omnichannel marketing, describe the advantages of omnichannel marketing and explain how retailers can best transition from multichannel marketing to omnichannel marketing.

The paper’s findings are based on a systemic review of the literature of academic studies, research-based studies by major consulting firms and case study reports of effective omnichannel retailers. The approach used is managerial and strategic.

Four stages are identified between a pure multichannel and a pure omnichannel marketing strategy. This multistage approach enables a firm to determine its current position, to view the gaps in its strategy in moving to the next level and to develop appropriate actions to move to the next higher level. This paper also identifies barriers to a firm implementing an omnichannel marketing strategy and describes how these barriers can be overcome.

This paper describes the advantages associated with omnichannel marketing and discusses a strategy to transition to omnichannel marketing. Barriers to adopting omnichannel marketing and how they can be overcome are analyzed.

This study makes a number of contributions to the literature on omnichannel marketing. It sets forth specific criteria for firms to determine their present stage on the multichannel marketing to omnichannel marketing hierarchy. This strategic approach provides firms with a roadmap to planning and implementing an omnichannel marketing orientation. The paper concludes with directions for future research and managerial implications and conclusions.

Vibration monitoring is being increasingly used as a tool for safe operation of machinery and efficient maintenance planning. There are, however, many problems associated with the measurement and interpretation of vibration data. In order to obtain a rapid diagnosis of a machine's health, and to apply condition monitoring results in practice, it is often necessary to consider the machine operating conditions, performance and other factors. These different approaches should be incorporated into one diagnostic technique having the proper balance of emphasis on each approach.