compressive strength of concrete is shown to be increased by the presence of salt or ocean salt in the mixing & curing water. the rate of strength gain is also affected when the concrete is cast & cured with saltwater & vice versa. Mixing concrete with saltwater increases the compressive strength rapidly & the strength was still increasing at 28 days. Preeti Tiwari (6) et.al In 2014 suggested that there was an
A mixture of hexasaccharide glycal and freshly activated 4 Å molecular sieve were treated with 1mL dimethyldioxirane (0.07 M) in 1 mL CH 2 Cl 2 at 0 ° C under nitrogen stream, and the residue was dried for 20 minutes under high vacuum power. Then, an azidohydrin solution was added to epoxide through a container in THF (0.8 mL) and cooled to - 40 ° C. Then, ZnCl 2 in Et 2 O (1 M, 25 μ L) was added, the mixture allowed to cool to room temperature, and then stirred for the next 12 hours. Then, the mixture was diluted by EtOAc (50 mL), was washed with NaHCO 3 saturated solu- tion (2 × 20 mL) and saltwater (10 mL), dried by Na 2 SO 4 , and the raw material purified by column chromatography (10%–22% EtOAc in hexanes) to provide 31.3 mg of coupled product in the form of a clear oil. To the solution of this product (0.013 mmol, 31.3 mg), 4-dimethylaminopyridine (0.013 mmol, 1.6 mg) and triethylamine (0.0219 mmol,
The need of new energy sources has led to a number of alternatives. Some better than others. One of those alternatives is energy created by transportation of solutions, osmotic energy or salinity gradient energy . In the osmotic process two solutions with different salt-concentrations are involved (often freshwater and salt-water). A semipermeable membrane, which is an organic filter, separates the solutions. The membrane only lets small molecules like water-molecules pass. The water aspires to decrease the salt-concentration on the side of the membrane that contains most salt. The water therefor streams through the membrane and creates a pressure on the other side . This pressure can be utilised in order to gain energy, for example by using a turbine and a generator.
Edge samples were evaluated due to the findings in this research regarding the accelerated degradation of both MOR and MOE over time compared to samples located at the center of the panels, and were thus the weakest link and the limiting factor for use. Table 2.19 shows that, with regards to the physical properties evaluated, MOR limits use as samples are out of compliance long before MOE loss becomes a factor. When comparing the water treatments, samples which were submerged in potable water fell below APA quality control guidelines after 8 hours of submersion, while saltwater submerged samples were out of compliance after 24 hours. This demonstrates the inequality in effect of varying water composition as well as showing the need for evaluation of OSB over a spectrum of times in order to understand this critical aspect of floods.
Prepare your students for this activity by talking about the water cycle. Explain how freshwater flows from the land to the ocean as runoff. Let them know that most of the runoff in cities flows into sewers. After storms, many coastal cities dump raw sewage into the ocean when their treatment facilities cannot handle the overflow. Rivers also discharge fresh water into the ocean. Regardless of its source, fresh water doesn’t mix with the ocean’s saltwater, but has a tendency to lie on top of the saltwater. Two layers of water are formed. This is very typical of what happens in estuaries. Even small differences in the degree of saltiness or salinity of seawater will cause the denisity to be different. After all, the difference between fresh and saltwater densities is very small-0.998 and 1.025 g/ml. Areas far from any large fresh water source can still have layers that form because one layer is more salty than the other. Density separates the layers because the more salt the water has in it, the more dense it is.
In this work, solar evaporation of saltwater is simulated using Ansys CFX. Due to solar radiation, saltwater gets evaporated and condensed in the surface of the cooled glass surface. Improved condensation can be achieved by passing cold water onto the surface of glass. Condensed water droplets were collected in a downcomer. Properties of water were analyzed. Simulation results were similar to experimental results. This result shows that CFD simulation is a powerful tool for parameter analysis and design of solar still.
Salt is obtained from two sources: rock salt and brine. Rock salt is simply crystallized salt, also known as halite. It is the result of the evaporation of ancient oceans millions of years ago. Large deposits of rock salt are found in the United States, Canada, Germany, Eastern Europe, and China. Sometimes pressure from deep inside the Earth forces up large masses of rock salt to form salt domes. In the United States, salt domes are found along the Gulf Coast of Texas and Louisiana. Brine is water containing a high concentration of salt. The most obvious source of brine is the ocean, but it can also be obtained from salty lakes such as the Dead Sea and from underground pools of saltwater. Large deposits of brine are found in Austria, France, Germany, India, the United States, and the United Kingdom. Brine may also be artificially produced by dissolving mined rock salt or by pumping water into wells drilled into rock salt. Natural brines always contain other substances dissolved along with salt. The most common of these are magnesium chloride, magnesium sulfate, calcium sulfate, potassium chloride, magnesium bromide and calcium carbonate. These substances may be as commercially valuable as the salt itself. Rock salt may be quite pure, or it may contain various amounts of these substances along with rocky impurities such as shale and quartz. For table salt, however, additives are usually mixed in. Most table salt
this electrolyte gains a progressively more structured en- vironment. The salt-triglycine and salt-water interactions enhance the overall structure of the solvent resulting in the increased viscosity B-coefficient with increase in salt molality.
ABSTRACT: Population’s exponential growth along with drought has increased water resources limitation, especially in arid and semi-arid area. Therefore, the use of non-conventional water is an important tool for water resource management. If unconventional water has no negative impact on soil properties and water, it can be used for irrigation coupled with desertification projects. So, this paper tries to present the effect of irrigation with municipal wastewater, saltwater, brackish water, and combination of salty water and wastewater on some soil properties including nitrogen, phosphorus, and potassium in Qom plain. Soil samples were taken from agricultural land treated by wastewater, saline water, brackish water, combination of salty water, and wastewater and range land as control in five treatments from depths of 0-30 and 60-90 centimeter. The results showed that wastewater has increased the amount of N, P, and K to other treatments and control area. The concentration of potassium in surface layer of area treated by combination of salty water and wastewater with amount of 459.39 ppm has the most significant difference to control and other treatments. Also, the maximum amount of nitrogen was observed in sub layer of saline and brackish water treatment with amount of 0.08 percent.
Students design and conduct a laboratory process to determine the effect of acid rain on hard water, soft water, and saltwater. These three types of water are representative of naturally occurring water bodies such as river water, spring water, and sea water. The observation and analysis of their data will lead students towards societal issues and personal as well as civic responsibility. The context of this learning experience is towards the end of the chemistry course after the topic of acids and bases.
appeared, 1000 ml of 0, 50 mM and 100 mM NaCl solutions were applied in each pot up to 60 days. Salt solutions were prepared by dissolving calculated amount of commercially available NaCl with tap water. Tap water was used as the control. The salt solution was applied stepwise with an increment of 25 mM in every alternate day till respective concentrations were attained. Treatment solutions were applied in excess so that the extra solution dripped out through the holes made at the bottom of the pots. Uppermost fully developed leaves were collected at 15, 30, 45, and 60 days after treatment
to reduce measurement uncertainty and improve the model’s reliability. Generally, two kind of sensitivity analysis can be distinguished: a global sensitivity and a local sensitiv- ity analysis (Tiemeijer et al., 2007; Spear and Hornberger, 1980). With local techniques parameter interdependencies are ignored and were found to be unreliable for non-linear relationships between parameters and outputs which are typ- ical for hydrological outputs (Tiemeyer et al., 2007; Muleta and Nicklow, 2005). Therefore, we used the above described GLUE method for a global sensitivity analysis where all pa- rameters are varied at the same time. The global sensitiv- ity of the parameters for the model output was determined in two ways. First, the global sensitivity of parameters for the total model behaviour was determined. We applied the GLUE method using the same cut-off criteria (Table 3) but with wider prior parameter ranges (indicated as GA-B, Ta- ble 2). In contrast with non-sensitive parameters which show uniform posterior distributions close to their prior distribu- tions, the sensitive parameters show large deviations. The Kolmogorov D statistics for testing of differences in distribu- tions was used as measure of the parameter sensitivity (van Huissteden et al., 2009; Roux and Dartus, 2006). The inter- dependencies of the model parameters were quantified by the determination of correlation between all behavioural param- eter combinations (expressed in R 2 ). Strong interdependen- cies (indicated by a large R 2 ) also revealed which parameters were sensitive to the total model response. Second, we tested the global sensitivity of the model parameters for the individ- ual model output. We calculated R 2 between parameter val- ues and model output errors for total water volume, total salt load, and mean salt concentration for the entire simulation period ( C(tot)). In addition, R 2 was calculated between pa- rameter values and model errors on measurement time scale ( C(dyn)). To focus on this short time scale, for this analysis we used only behavioural parameter sets with absolute errors in the total water and salt balance and mean concentrations which were smaller than 5 %. This GLUE analysis is indi- cated as GA-C.
Abstract: Ground water is, as a rule, continuously seen as a dependable wellspring of supply to satisfy the requirements of residential water system and mechanical sections of the country. The progression practices during the years have ominously impacted the ground water dominion in various areas of the country. Seawater intervention or the movement of brine into the fresh formation zone will increment groundwater saltiness, posing an enormous ecological effect in coastal regions universally. Ocean level ascent and decrease in groundwater levels due to over usage may end up in saline water intervention; moving major ions and nutrients in groundwater. “Saltwater invasion is the biggest and much debated water story in the world these days. It’s a silent problem. It’s easy to ignore politically however it will ruin the water supply for future generations.” India’s water security is in a very unpredictable position. Even by conventional estimates, 40% of individuals in India won’t have drinking water by 2030. As indicated by an IBRD report, at least 21 Indian urban communities are heading towards zero groundwater level by 2020. Managed formation Recharge (MAR) could be an encouraging modification to the present lifestyle to cut back exposure to temperature change and hydrological variability. MAR can take a significant position as a measure to curb over-abstraction and to restore the groundwater balance. It can be utilized to recharge aquifers subject to decreasing yields, to control saltwater intervention or to prevent land collapse. MAR may likewise be employed to support or improve the working of ecosystems and the nature of groundwater.
Although experimental studies can provide useful insight into membrane-based pro- cesses, the underlying mechanisms governing such processes occur at the molecular scale and thus cannot be directly probed through macro-scale experiments. MD simulations can provide atomic-scale mechanistic details of water and salt transport in membranes. A recent review has shown extensive applications of MD simulations in studying mem- brane material properties and molecular transport of water and ions through membranes . Membrane-based processes are typically simulated using either equilibrium or non- equilibrium MD (NEMD) simulation procedures. Equilibrium MD simulations usually involve the computation of transport properties from a system with no chemical potential between the two sides of the membrane . In NEMD, a pressure gradient is created by applying external forces to selected atoms in the feed water [40, 41] or by the use of an external piston . Simulation results based on the available studies have played a criti- cal role in elucidating fundamental mechanisms governing water and ion transport as well as the microscopic interactions between membranes and solutes. The application of MD simulations in studying diffusion, adsorption, fouling and water transport in membranes has provided realistic results which have been in fair agreement with experimental data in some cases.