14 research outputs found
Materials and Corrosion in Seawater Reverse Osmosis Plants: A Review
Desalination is emerging as one of the most promising solutions to extraction and increasing global demand for drinking water. A water purification process called reverse osmosis (RO), in which dissolved solids are separated from solutions by partially permeable membranes. Advances in membrane technology have resulted in the removal of up to 99% of salts in seawater. However, the process and system of seawater treatment RO are associated with many problems, such as scaling and fouling of the membranes, corrosion of the pumps, valves and piping system due to the highly concentrated salt solution and high chemical consumption. Nowadays, these problems have become very critical as they severely affect the desalination process and also massively deteriorate the performance and lifetime of the system components and materials. To ensure that the desalination process is always the best option for a low-maintenance, highly efficient and cost-effective system and process, a comprehensive study of these problems is essential. Therefore, this article addresses the characteristics of metallic materials and corrosion problems in the reverse osmosis process of seawater desalination, as well as the best solutions to focus on and evaluate for an optimal seawater desalination process, and the selection of the category of duplex stainless steels suitable for seawater desalination plants to reduce maintenance, avoid plant shutdown and ensure plant safety
Water Hammer Analysis in Water Pipelines and Methods for Protection
In water processing industry, pressurised pipeline problems bring dangerous consequences, causing flooding, traffic accidents or death, financial and material losses and the disruption of the water supply. There are some problems in water pressurised pipelines system occur gradually, and some problems occur in very sudden without any warning with massive impacts and harms. Most of the sudden events that affect water system and municipal operation and maintenance centres are the phenomenon of sudden explosions and cracks in water pipes which lead to disaster. The phenomenon of water hammer is as a result of imperfect design or poor operation methods. The transition in the pressurised pipeline from one steady state to another steady state such as from a constant velocity to another velocity without a protection system make huge in pressure change. Any change in velocity leads to a pressure changes in very short time will cause to disaster strikes for the system stabilization. Professional design of liquid pipelines and proper selection of materials prevents the phenomenon of water hammer. Therefore, in this paper, the important issues on water hammer, protection systems and professional planning with special software programmes such as Allievi software was addressed
An integrated technique using solar and evaporation ponds for effective brine disposal management
Desalination is a process that involves the removal of salts and non-ionic minerals from seawater to produce freshwater that is fit for human consumption. This process produces brine, which is typically redisposed into the sea. The relatively high salt concentration in the disposed brine increases the salinity of water and soil, which adversely affects the environment. However, brine is found to be rich in economically valuable minerals. In order to effectively manage the disposed brine, this study proposes an integrated technique using solar and evaporation ponds to filter valuable minerals from concentrated brine. The results of this study demonstrate that the proposed technique can be effectively employed for this purpose. Furthermore, this helps reduce desalination costs and complies with the notion of renewable energy production and eco-friendliness
Characteristics and economic value of the rejected brine at Al-Khobar desalination plant in KSA
This paper presents the characteristics of seawater and rejected brine, and the economic value of the rejected brine at Al-Khobar desalination plant, KSA. The rejected brine may be discharged to sea/ocean contains of different salts and dissolved minerals in high concentrations, which carry considerable economic value in relevant industries. It is found that the rejected brine contains huge amount of SO42-, Cl-, Na+, Ca2+, Mg2+, K+, Fe2- and Cu2+, which have high economic value. Therefore, these minerals can be recovered directly from the rejected brine. This study estimated the quantities of these minerals and the revenue income according to their current market prices. Moreover, this study may help the policy/decision makers to assess the economic value of the brine to establish new industries for brine processing. Seawater and brine samples collected from the Al-Khobar plant. Various physical and chemical properties were observed in order to find economic value of minerals
The development and applications of solar pond: a review
Solar energy is a substantial source of clean and renewable energy. Recently, solar pond technology has made a great progress due to the fact that solar ponds can collect and store heat in the same time which has reduced the cost significantly thus making it an area of interest for the industry and researchers. Several salt gradient solar ponds have been constructed in many regions around the world. This paper reviews the various schemes of solar ponds, in addition to their performance, optimization, heat extraction mode and applications as reported in the literature. The maintenance and cost effect on solar pond have also been discussed
The Impact of Corporate Governance on the Continuity of Family Businesses in Saudi Arabia
In small villages, in cities booming with commerce, in remote fishing communities, and massive marketplaces, in tropical destinations, and in corners of the globe few have ever visited, one is always able to find family businesses. From small wares being sold to neighbors, to huge corporations with billions in assets, families hold and always have held a segment of the global market that cannot be ignored. While family businesses have existed throughout history, legal advice and governance specifically geared toward them, which holds the success of the family business at the center of the laws, has never been a focus of those regulating the family corporations.
This research studies the best corporate governance frameworks and focuses on finding the best practical solutions for family businesses in Saudi Arabia which operates under Sharia Law. Sharia Law defines “The entire religion (Islam), which Allah has chosen for his servants to bring them forth thereby from the depths of darkness into the light. It is what He has prescribed for them and what He has explained to them of commands and prohibitions, halaal and haraam.” A family enterprise governed by local, national, and global laws and also operating under the beliefs of Sharia Law faces a whole host of potential conflicts. While family businesses of all sizes, listed or unlisted in the Stock Market, will face these similar issues and challenges, for the purposes of this research high-mid and larger businesses will be the primary focus, but it should be noted that the problems described here are not exclusive to the highest earning family corporations, but do in fact affect them all. Appropriate governance of family enterprises will keep the entrepreneur, their family, the employees, partner or investors, stakeholders or shareholders, suppliers, and contractor’s best interests in mind, while also staying aware of the unique relationships within the founding family, and ideally be applicable across many markets including those governed by Sharia Law, such as within Saudi Arabia.
Lawyers have a responsibility to understand the businesses they are advising, and lawmakers have to serve their constituency by vesting themselves in understanding all aspects of the laws they consider. To consider laws regarding businesses, they must research the various businesses they will potentially be passing or denying laws over. This paper serves to show how a better knowledge of the beliefs, culture, and traditions a family holds closely to, along with focusing on the success and growth of enterprises specifically held by families, can give lawyers and consultants new and valuable insights. This more well-rounded perspective is sure to benefit the family owned businesses and lead them into a better future.
When lawyers consider the unique challenges faced by family businesses, they will be better able to both advise and guide them. Agency cost, relationships between family members, ownership vs management, and other issues all affect family businesses more acutely than corporately owned enterprises. As lawyers recognize these factors, they will develop a great understanding and also be more prepared to help the families they work with
Laminin Regulates Fibronectin Levels In The Zebrafish Myotendinous Junction Via Matrix Metalloproteinase-11
In the present study, we utilized zebrafish (Danio rerio) embryos and larvae to enhance our understanding of the myomatrix changes during muscle development. Previously, it has been shown that there is a dramatic downregulation of Fibronectin (Fn), during somitogenesis at myotendinous junctions (MTJs). Fn is one key component of Extracellular Matrix (ECM) and plays an essential role for both somite and early muscle development. The replacement of Fn-rich matrix with laminin-rich matrix is essential for normal function of the myotome. Here we investigate the mechanism of Fn degradation during myomatrix remodeling in embryonic stage of zebrafish.
We show that laminin polymerization indirectly promotes Fn degradation at the MTJ, via a matrix metalloproteinase 11(Mmp11)-dependent mechanism. Laminin polymerization is required for both expression and localization of Mmp11 to the MTJ, where Mmp11 is necessary and sufficient for Fn degradation in vivo. Furthermore, reduction of residual Mmp11 in laminin mutants promotes Fn-rich MTJ that partially rescues skeletal muscle architecture.
These results identify a mechanism for Fn degradation at the MTJ, highlight crosstalk between different ECM proteins, and identify a new in vivo function for Mmp11. Taken together, our data demonstrate a novel signaling pathway mediating Fn degradation, revealing new regulatory mechanisms that guide ECM remodeling during morphogenesis in vivo. These data can be manipulated in many human pathological conditions in which Fn is dysregulated to improve muscle tissue structure and function
The development and applications of solar pond: a review
Solar energy is a substantial source of clean and renewable energy. Recently, solar pond technology has made a great progress due to the fact that solar ponds can collect and store heat in the same time which has reduced the cost significantly thus making it an area of interest for the industry and researchers. Several salt gradient solar ponds have been constructed in many regions around the world. This paper reviews the various schemes of solar ponds, in addition to their performance, optimization, heat extraction mode and applications as reported in the literature. The maintenance and cost effect on solar pond have also been discussed
Lysosomal Function Impacts the Skeletal Muscle Extracellular Matrix
Muscle development and homeostasis are critical for normal muscle function. A key aspect of muscle physiology during development, growth, and homeostasis is modulation of protein turnover, the balance between synthesis and degradation of muscle proteins. Protein degradation depends upon lysosomal pH, generated and maintained by proton pumps. Sphingolipid transporter 1 (spns1), a highly conserved gene encoding a putative late endosome/lysosome carbohydrate/H+ symporter, plays a pivotal role in maintaining optimal lysosomal pH and spns1−/− mutants undergo premature senescence. However, the impact of dysregulated lysosomal pH on muscle development and homeostasis is not well understood. We found that muscle development proceeds normally in spns1−/− mutants prior to the onset of muscle degeneration. Dysregulation of the extracellular matrix (ECM) at the myotendinous junction (MTJ) coincided with the onset of muscle degeneration in spns1−/− mutants. Expression of the ECM proteins laminin 111 and MMP-9 was upregulated. Upregulation of laminin 111 mitigated the severity of muscle degeneration, as inhibition of adhesion to laminin 111 exacerbated muscle degeneration in spns1−/− mutants. MMP-9 upregulation was induced by tnfsf12 signaling, but abrogation of MMP-9 did not impact muscle degeneration in spns1−/− mutants. Taken together, these data indicate that dysregulated lysosomal pH impacts expression of ECM proteins at the myotendinous junction
Lysosomal Function Impacts the Skeletal Muscle Extracellular Matrix
Muscle development and homeostasis are critical for normal muscle function. A key aspect of muscle physiology during development, growth, and homeostasis is modulation of protein turnover, the balance between synthesis and degradation of muscle proteins. Protein degradation depends upon lysosomal pH, generated and maintained by proton pumps. Sphingolipid transporter 1 (spns1), a highly conserved gene encoding a putative late endosome/lysosome carbohydrate/H+ symporter, plays a pivotal role in maintaining optimal lysosomal pH and spns1−/− mutants undergo premature senescence. However, the impact of dysregulated lysosomal pH on muscle development and homeostasis is not well understood. We found that muscle development proceeds normally in spns1−/− mutants prior to the onset of muscle degeneration. Dysregulation of the extracellular matrix (ECM) at the myotendinous junction (MTJ) coincided with the onset of muscle degeneration in spns1−/− mutants. Expression of the ECM proteins laminin 111 and MMP-9 was upregulated. Upregulation of laminin 111 mitigated the severity of muscle degeneration, as inhibition of adhesion to laminin 111 exacerbated muscle degeneration in spns1−/− mutants. MMP-9 upregulation was induced by tnfsf12 signaling, but abrogation of MMP-9 did not impact muscle degeneration in spns1−/− mutants. Taken together, these data indicate that dysregulated lysosomal pH impacts expression of ECM proteins at the myotendinous junction