Development of a green corrosion inhibitor for use in acid cleaning of MSF desalination plan

A green and cost-effective inhibitor based on Date palm leaves extract was formulated for use during acid cleaning of thermal desalination plants. The inhibitor formulation designated as F1 was tested against the corrosion of ferrous-based alloys namely: carbon steel, Ni-resist, and 316L stainless steel in 2% HCl solution at 40 °C under static and hydrodynamic conditions. Weight loss and electrochemical methods complemented with scanning electron microscopy were used in the study. Experiments were performed for 6, 24, and 72 h and the performance of F1 was compared with that of a commercial acid corrosion inhibitor. F1 exhibited excellent corrosion inhibition performance. Under static and dynamic conditions, 0.4% of F1 provided excellent corrosion inhibition up to 72 h and comparable to the commercial inhibitor performance. The inhibitors (F1 and the commercial one) exhibited a behavior typical of a mixed type corrosion inhibitor in the studied environment according to the potentiodynamic polarization. Results from cyclic potentiodynamic polarization experiments excluded pitting corrosion risk on the 316L stainless steel in the studied medium. Results from all applied techniques are in good agreement

Dynamic replication strategies in data grid systems: A survey

In data grid systems, data replication aims to increase availability, fault tolerance, load balancing and scalability while reducing bandwidth consumption, and job execution time. Several classification schemes for data replication were proposed in the literature, (i) static vs. dynamic, (ii) centralized vs. decentralized, (iii) push vs. pull, and (iv) objective function based. Dynamic data replication is a form of data replication that is performed with respect to the changing conditions of the grid environment. In this paper, we present a survey of recent dynamic data replication strategies. We study and classify these strategies by taking the target data grid architecture as the sole classifier. We discuss the key points of the studied strategies and provide feature comparison of them according to important metrics. Furthermore, the impact of data grid architecture on dynamic replication performance is investigated in a simulation study. Finally, some important issues and open research problems in the area are pointed out

Three-level NPC Converter-based Neuronal Direct Active and Reactive Power Control of the Doubly Fed Induction Machine for Wind Energy Generation

In this paper, neuronal direct power control (DPC) strategy is applied for a doubly fed induction generator (DFIG) based wind energy generation system. Used in three level neutral point clamped (NPC) rectifiers, to directly control the active and reactive power, switching vectors for rotor side converter were selected from the optimal switching table using the estimated stator flux position and the errors of the active and reactive power, also the grid side is controlled by direct power control based a grid voltage position to ensure a constant DC- link voltage. This approach is validated by using MATLAB/SIMULINK software and simulation results can prove the excellent performance of this control as improving power quality and stability of wind turbine