The use of a proper leak detection system in pipelines is of crucial importance in water transmission systems. In these methods, we should consider the time and accuracy of leak detecting procedure for preventing energy loss and reducing environmental impacts. In these days, seawater transmission lines are used for cooling systems, and for injecting water into the oil wells to improve oil recovery. Due to the more environmental impacts of saltwater, the leak detection system must have appropriate accuracy and speed in leak detection. The purpose of this paper is to choose a leak detection system for a saltwater transmission line. First of all, the specifications of different leak detection systems are provided. Finally, according to the mentioned project conditions, the most suitable method-fiber optic system-is recommended for these conditions. The most important advantages of this system are high accuracy, rapid leak detecting, and the ability of online monitoring of other parameters, such as temperature distribution or detecting intrusion into the buried line areas. These abilities result in improving safety and optimizing operating costs.

This article presents advancements in the working of Single slope conventional solar still (CSS) through the integration of saltwater bottles. The saltwater contained within these bottles (totalling 40 in number) is dyed black to enhance its solar radiation absorption ability. Using their high heat capacity, these bottles efficiently store solar energy during peak radiation hours, subsequently releasing it during the evening or nocturnal periods. Results have demonstrated a consistent increase in the temperature of water within the Modified solar still (MSS) compared to its typical counterpart, notably observed after 14:00 h. Moreover, the cumulative yield obtained from the MSS surpasses that of the CSS variant by 25.4%. Augmentation with saltwater bottles has increased the efficiency of MSS by 25% as compared to the CSS. Furthermore, incorporation of saltwater bottles results in a notable reduction in the cost of distillate production, with a decline of 20%, as compared to the CSS. The study emphasises how using saltwater bottles as thermal energy storage reservoirs in solar distillation systems could have real-world applications. The results offer important information on enhancing the effectiveness and economic viability of water purification, especially in areas where there are issues with water scarcity.

There is a close connection between saltwater intrusion into aquifers and groundwater extraction. Freshwater extraction in coastal aquifers is one of the most important reasons for the saltwater intrusion into these aquifers. Condition of extraction system such as well depth, discharge rate, saltwater concentration and etc. could affect this process widely. Thus, investigating different extraction conditions comprises many management advantages. In the present study, the effects of freshwater extraction on saltwater interface displacement have been investigated in a laboratory box. Three different well depths (H) were considered with combinations of 3 different extraction rates (Q) and 3 saltwater concentrations (C) for detailed investigation of the effects of these factors variations on saltwater displacement. SEAWAT model has been used to simulate all the scenarios to numerically study of the process. The experimental and numerical results showed that when the C and Q rates were small and the well depth was shallow, the saltwater interface wouldn’t reach the extraction well, so the extracted water remained uncontaminated. When the C and Q rates were increased and the well was deepened, the salinity of the extracted water became higher. When the Q and C rates were high enough, in the shallow well depth, the final concentration of the extracted water was low but a huge part of the porous media was contaminated by the saltwater, furthermore when the well was deepened enough, the final concentration of the extracted water was increased but a small part of the porous media was contaminated by the saltwater. Finally, the results showed that when the Q and H rates were high enough, the extraction well behaved like a barrier and didn’t allow the advancing saltwater wedge toe to be intruded beyond the wells.

Four halotolerant fungal isolates originating from the saltwater Lake Urmia in Iran wereselected during a screening program for salt resistance and a-amylase activity. The isolates were identified based on sequencing the ITS region and a part of the β -tubulin gene, as Penicillium chrysogenum (isolate U1; CBS 132820), Fusarium incarnatum (isolate U2; CBS 132821), and Penicillium polonicum (isolate U3; CBS 132822, and isolate U4; CBS 132823). The growth of these isolates was determined by measuring the colony diameter and mycelia dry weight in Sabouraud dextrose agar and yeast nitrogen base medium supplemented with NaCl, KCl, and LiCl. Isolate U4 showed a growth up in 15% NaCl and U1 was the only isolate that could grow in 20% KCl. None of the strains grew in a media containing LiCl. The salt supplemented medium did not increase the size of colony diameter in all isolates (p>0.05). The ability of the selected isolates for amylase production was quantitatively tested and showed that P. polonicum isolate U4 was the most potent producer of amylase with a yield of 260.9 U/L after 60 h, whereas P. polonicum isolate U3 was the lowest one with a production level of 97.9 U/L after 48 h. P. polonicum isolate U4 could be a suitable candidate for production of amylase on an industrial scale after optimization.

Introduction: Coastal aquifers are the main source of freshwater supply in most coastal regions. Their proximity to seas and oceans exposes them to the risk of salinization. Hence, providing an effective solution to reduce saltwater intrusion can play a significant role in coastal water resource management. In this study, an effort was made to evaluate the effects of recharge wells and abstraction wells as hydraulic barriers, and cutoff walls as a physical barrier, both separately and in combination, on the mitigation of seawater intrusion using different experiments.Methodology: The experimental model used in this study was a flow tank with a thickness of 1 centimeters. The flow tank was divided into a central chamber with internal dimensions of 140×58×5 centimeters and two side chambers with internal dimensions of 10×58×5 centimeters. The central chamber served as the porous medium, while the left and right side chambers were used to control the head of saline and fresh water entering the porous medium during the experiments. Glass beads were employed to create the porous medium. The fresh water used in the experiments was supplied from the tap water, with a density of approximately 998 kg/m3. The saline water used in the experiments was prepared by adding 35 grams of purified salt and 2 milliliters of red food coloring to each liter of tap water. An aluminum sheet with a thickness of 7 millimeters, an approximate width of 5 centimeters, and a height of 54 centimeters was used to construct the cutoff wall. Two separate polyvinyl chloride (PVC) pipes were used as extraction and injection wells. The extraction well was placed 22 centimeters from the saltwater boundary, with its mouth penetrating to a depth of 52 centimeters from the top edge of the experimental model. The injection well was placed 40 centimeters from the saltwater boundary, with its mouth penetrating to a depth of 56 centimeters from the top edge of the model. To prepare the required freshwater for the injection well, one cubic centimeter of blue food coloring was added to each liter of tap water.Results and Discussion: In this study, injectioning action was performed at flow rates of 0.65, 1.30, and 2.0 liters per minute. The fed water flow caused the return of the salt wedge. The reason is that when the injection well is activated, the local velocity in the aquifer increases because the recharge flow accumulates with the normal velocity inside the aquifer, resulting in a greater velocity at the outlet of the well towards the saltwater boundary. This increased flow washes and transports salt grains of the salt wedge along the common boundary towards the sea, leading to their removal from the porous medium. Thus, greater local velocity, the greater the washing and salt transport, resulting in a smaller salt wedge or, in other words, a greater return. For investigating the combined effect of cutoff walls and injection wells, the intrusion experiment was first conducted in the presence of a cutoff wall. Therefore, the distance of the salt wedge to the saltwater boundary was 38.5 centimeters. Then, injectioning action started at a rate of 0.65 liters per minute. The injected water began to move within the porous medium, and after approximately 50 minutes from the start of the injectioning process, the salt wedge reached a stable state. In the stable conditions, the length of the salt wedge was 27 centimeters, indicating a return of 17 centimeters. Therefore, the effectiveness of the simultaneous use of an cutoff wall and a injection well in preventing saltwater intrusion is approximately 38.6%. To investigate the combined effect of injection and extraction wells in reducing saltwater intrusion, both wells were activated simultaneously at a rate of 0.65 liters per minute each. After about 35 minutes, the salt wedge reached a stable state with a length of 29.6 centimeters, indicating a return of approximately 16.7 centimeters. Thus, the simultaneous use of extraction and injection wells at a rate of 0.65 liters per minute each is approximately 32.7% more effective than using the extraction well alone.Conclusion: The simultaneous use of extraction and injection wells showed a 5.22% better performance in preventing saltwater intrusion compared to using the extraction well alone, albeit with approximately 2% lower effectiveness in retreating the salt wedge compared to using the injection well alone. By comparing the combined effect of all three barriers with each individual method, it was evident that the combined method of cutoff wall, extraction well, and injection well had a better performance in preventing saltwater intrusion by 17% and 19.3% compared to the cutoff wall and extraction well alone, respectively. However, their effectiveness was 4.59% weaker compared to the individual effect of the injection well.

Groundwater is one of the most important sources of drinking, industrial, and agricultural water in arid and semi-arid regions, where the occurrence of droughts, rapid population growth, and the corresponding increase in water demand threaten groundwater resources. Over-exploitation and mismanagement of groundwater resources result in environmental problems such as subsidence and saltwater intrusion in coastal aquifers. The risk of saltwater intrusion threatens the Urmia aquifer due to the proximity of the aquifer to Lake Urmia and severe groundwater decline. This study evaluates the vulnerability of saltwater intrusion by the GALDIT framework. The results show the conservative vulnerability index with low efficiency, where vulnerable areas are limited to a narrow strip near the coastline. Fuzzy membership functions were employed within the GALDIT framework to increase efficiency. The results of the modified GALDIT resolve the weakness of presenting conservative results in the basic GALDIT framework.

From 2014 in the duration of 24 months, A total of 172 specimens of 29 fish species of saltwater ornamental fish ones offered for sale in shops in Tehran province which showed symptoms of illness were caught from aquarium and transferred alive to the laboratory. After biometry (total length measurement) biopsy and wet spread from the skin and the gills of the fish were supplied and examined under photomicroscope (Olympus ch20 bimf200) in the lab. Among the caught species 76.7 % had parasites infection in their skin and gills and 23.3 % were free of such as infection and of the infected fish, the outer layer of the skin showed the most infection by 97.7 %. Ciliated protozoan parasite (Cryptocaryon irritans) most infection and respectively monogene (Benedinia sp) and flagellate protozoan parasite (Amyloodinium ocellatum) and Turbellarian Sp worms with and ciliated protozoan Parasite (Urinema marinum) and crustacea parasite (Ergasilus sp)and Ciliated protozoan parasite (Euplotes sp) and Ciliated protozoan parasite (Brooklynella sp) and monogene(Dactylogyrus sp) parasite and Ciliated protozoan parasite (Trichodina sp) showed the least infection. This is the first report of saltwater fish parasites mentioned in Iran. The aim of this study is to know external parasites in some saltwater ornamental fish in Tehran Province.

Steady and unsteady experimental and numerical simulations are carried out in this paper to investigate saltwater intrusion mechanism into unconfined coastal aquifer. Laboratory results are compared to dispersive SEAWAT model to assess the applicability of numerical simulation. The dispersive SEAWAT model predicts salinities reasonably well comparing with sand-tank observation but it over predicts salt wedge toe position. Time reaching to steady state was almost equal in both physical and numerical modeling. In order to compare the mixing zone thickness, 5% and 95% salinity contours were also compared against laboratory data. The numerical results indicated partially wide mixing zone that is not observed in the experiments. Longitudinal dispersivity has been calibrated in the model to minimize the mixing zone thickness. Flow velocity components are also computed in this study by simple Darcy’s law and the freshwater and saltwater streamlines are depicted to visualize the flow adjacent the salt wedge and to observe the freshwater/saltwater movement toward exit point.