Sodium Chloride Salt Concentrations Research Articles

The Impact of Salinity, Putrescin, and Melatonin Interactions on Green Bean Vegetative Indicators

This study aims to assess the effect of salt stress by using concentrations of sodium chloride (0, 40, 20, 60) mmol. L-1. Putrescine (0.2 and 0.4) mmol. L-1 and Melatonin (0.2, 0.4) mmol. L-1 and their overlap in some physiological and phenotypic traits of a green bean plant. The experiment was carried out using a complete randomized design (CRD) as a two-factor experiment (putrescine and melatonin x sodium chloride salt concentrations). The results were statistically analyzed with 10 replications that included 20 root tips for each treatment, and the averages were compared using the least significant difference at the 0.05 probability. The results showed that the effect of salt stress led to a significant decrease in most of the studied traits, a concentration of 60 mmol. L-1 led to a decrease in the percentage of plant survival by average branch length, number of shoots, dry weight percentage, and chlorophyll content. Also, adding melatonin significantly increased most of the studied traits using concentrations of 0.2 and 0.4 mmol. L-1 compared to adding putrescin (0.2), as the average branch length increased by increase, the number of shoots, the survival rate of plants, the dry weight, and the percentage of chlorophyll. The experiment’s results also showed a significant effect of the interaction between salt stress and melatonin on most of the vegetative growth characteristics of green beans. The effect of putrescine led to a decrease in vegetative indicators due to its high concentration in the medium used in the experiment.

Characterization of cavitation under ultrasonic horn tip – Proposition of an acoustic cavitation parameter

Acoustic cavitation, generated by a piezo-driven transducer, is a commonly used technique in a variety of processes, from homogenization, emulsification, and intensification of chemical reactions to surface cleaning and wastewater treatment. An ultrasonic horn, the most commonly used acoustic cavitation device, creates unique cavitation conditions under the horn tip that depend on various parameters such as the tip diameter, the driving frequency of the horn, its amplitude, and fluid properties. Unlike for hydrodynamic cavitation, the scaling laws for acoustic cavitation are poorly understood. Empirical relationships between cavitation dynamics, ultrasonic horn operating conditions, and fluid properties were found through systematic characterization of cavitation under the tip. Experiments were conducted in distilled water with various sodium chloride salt concentrations under different horn amplitudes, tip geometries, and ambient pressures. Cavitation characteristics were monitored by high-speed (200,000 fps) imaging, and numerous relations were found between operating conditions and cavitation dynamics. The compared results are discussed along with a proposal of a novel acoustic cavitation parameter and its relationship to the size of the cavitation cloud under the horn tip. Similar to the classical hydrodynamic cavitation number, the authors propose for the first time an acoustic cavitation parameter based on experimental results.

Protocol Optimization of DNA Extraction from Banana Fruits

Background: DNA extraction is the process by which the DNA is extracted and purified from the living or dead cells or tissues. There are many different kits commercially available for DNA extraction, with varying protocols. This study aimed at determining the optimal conditions for the extraction of high yield DNA from banana fruits.
 Methodology: DNA was extracted from banana fruits by precipitation method. The DNA yield was determined using the Nanodrop DNA quantification technique.
 Results: The optimal sodium chloride salt concentration for DNA extraction from banana fruits was 4mM and the amount of DNA extracted increased as the temperature decreased. The highest yield was obtained between 4 0C to 0 0C.
 Conclusion: We report for the first time a protocol with an optimal salt concentration (NaCl, 4mM) for quality DNA yield from banana fruits. A critical consideration is required to establish an optimal range of moderate temperatures and DNA concentrations for better quality and desired yields. There may not be a universal protocol for DNA extraction from all plant materials.

Low-pressure reverse osmosis membrane made of cellulose nanofiber and carbon nanotube polyamide nano-nanocomposite for high purity water production

Cellulose nanofiber (CNF) and multiwall carbon nanotube (CNT) nanocomposite polyamide membranes were synthesized and used in a low-pressure reverse osmosis (RO) system. Incorporating CNT and CNF into the polyamide structure (PA-CNT/CNF) allows the homogenous dispersion within the polymeric matrix, increasing its hydrophobic character and surface oxygen functionalities while reducing its surface roughness when compared to plain polyamide (PA), PA-CNT, and PA-CNF membranes. The resultant nanocomposite was tested at 0.75 MPa and sodium chloride salt concentration of 500 ppm resulting in a rejection of 99.47 % and water permeability of 1.65 m3/m2day. The rejection and permeation performance is highly competitive compared with commercial RO membranes. A 2in spiral module built with the PA-CNT/CNF membrane and tested for SiO2, NaCl, and CaCl2 rejection showed a reduction in its permeability of 24.9 % after 100 h of operations, while the commercials showed a decrease of 49.42 %. The present RO membrane module achieved a calcium rejection of 97.5 % and a boron rejection of 50.4 %. The 2in PA-CNT/CNF spiral module was tested in a two-step RO filtration system for high pure water (HPW) production and compared with a TW30 module with NSF certification. The PA-CNT/CNF module revealed a permeability reduction of 9.07% after 30 h operation, while TW30 had a reduction of 20.3%, which is about twice the durability. Molecular dynamics simulation showed that the CNF increased water hydration and boron diffusion on the membrane while CNT increased charge transfer to the PA structure. This polymeric nanocomposite has potential use in producing high purity water for brackish water or wastewater reuse for applications in the emerging semiconductor or pharmacology industry.

The effect of pH and ionic strength on the adsorption of glyphosate onto ferrihydrite

Although, glyphosate (N-(phosphonomethyl) glycine) is one of the most widely used herbicides in the world, its interaction with poorly crystalline iron oxides, such as ferrihydrite, is not well studied. In this research, we examined the adsorption of glyphosate onto ferrihydrite using infrared spectroscopy (FT-IR), electron paramagnetic resonance spectroscopy (EPR), adsorption kinetic models and adsorption isotherm models. The effect of pH and sodium chloride concentration on the adsorption of glyphosate onto ferrihydrite as well as the effect of extractors (CaCl2 0.010 mol L−1 and Mehlich) on the desorption of glyphosate were also evaluated. There are two important findings described in this work. First, 84% of adsorbed glyphosate strongly interacted to ferrihydrite as an inner-sphere complex and phosphate and amine groups are involved in this interaction. Second, an increase of sodium chloride salt concentration increased the adsorption of glyphosate onto ferrihydrite. The non-linear Langmuir model and pseudo second order model showed a good agreement of theoretical limit of glyphosate adsorbed onto ferrihydrite, 54.88 µg mg−1 and 48.8 µg mg−1, respectively. The adsorption of glyphosate onto ferrihydrite decreased when the pH increased. Under the conditions used in this work, EPR spectra did not show dissolution of ferrihydrite. Surface area, pore volume and pHpzc of ferrihydrite decreased after adsorption of glyphosate.

Evaluation of the influence of salt concentration on cement stabilized clay by electrical resistivity measurement method

The influence of salt concentration on the cementation process of cement stabilized clay is studied using the electrical resistivity measurement. The clay with various sodium chloride salt concentrations was prepared artificially and stabilized by Ordinary Portland cement with different contents. A series of electrical resistivity tests and unconfined compressive strength tests of cement stabilized clay specimen after curing for 28days were carried out. The electrical conductivity and pH value of pore fluid of the cement stabilized clay were also measured, and the microstructure of the samples was investigated by a scanning electron microscope. The results indicate that a high salt concentration has a detrimental effect on the unconfined compression strength of cement stabilized clay and results in a low electrical resistivity. A good linear relationship between the unconfined compression strength and the electrical resistivity of cement stabilized clay was observed. A unique exponential func'tion well adapts electrical resistivity values with cement content and salt concentration. The porosity-salt concentration/cement content ratio is an appropriate parameter to assess the electrical resistivity of the cement treated salt-rich soil investigated. The electrical resistivity measurement can be used as a non-destructive and both time and cost effective method to evaluate the quality of cement stabilized soft clays in practice.

Experimental Investigation of Unconfined Compression Strength and Stiffness of Cement Treated Salt-Rich Clay

Soft clay with high sodium chloride salt concentration is a problem encountered by geotechnical and highway engineers. Chemical stabilization using cement is an attractive method to improve the engineering properties of soft soil. However, very limited studies have been conducted to reveal the effect of salt concentration on the engineering properties of cement-stabilized soil and the reported results in literature are not consistent. The impact of sodium chloride salt on the strength and stiffness properties of cement-stabilized Lianyungang marine clay is studied in this study. The clay with various sodium chloride salt concentrations was prepared artificially and stabilized by various contents of Ordinary Portland cement. A series of unconfined compressive strength (UCS) tests of cement stabilized clay specimen after 7, 14, and 28 days curing periods were carried out. The results indicate that a high sodium chloride salt concentration has a detrimental effect on the UCS and stiffness of cement-stabilized clay. The detrimental effect of salt concentration on the strength and stiffness of cement-stabilized clay directly relates to cement content. Soils mixed with high cement content are more resistant to the negative effect of salts than soils mixed with low cement content. The ratio of modulus of elasticity to UCS of cement treated soil does not have an obvious relationship with salt concentration. The findings of this study present a rational basis for the understanding of the impact of salt on the engineering properties of cement-treated soil.

Self-sustained webs of polyvinylidene fluoride electrospun nanofibers at different electrospinning times: 2. Theoretical analysis, polarization effects and thermal efficiency

A novel theoretical model that considers the gas transport mechanisms through the inter-fiber space of self-sustained electrospun nanofibrous membranes (ENMs) is developed for direct contact membrane distillation (DCMD). The theoretical model involves the structural characteristics of the ENMs, the heat transfer mechanisms and the nature of mass transport through the self-sustained web. The permeate fluxes of different ENMs prepared with different electrospinning times and therefore different thicknesses were predicted for different feed temperatures and sodium chloride salt concentrations up to 60g/L. The used ENMs exhibit different parameters such as liquid entry pressure of water, inter-fiber space, void volume fraction, thickness, etc. In contrast to what reported in other theoretical MD studies considering Bosanquet equation with equal mass transport contributions for Knudsen diffusion and ordinary molecular diffusion, in this study the contribution of each mass transport mechanism was determined. It was found that the Knudsen contribution increases with the increase of the ratio of the mean electrospun fiber diameter to the inter-fiber space. The predicted permeate fluxes were compared with the experimental ones and reasonably good agreements between them were found. The temperature polarization coefficient (θ) and the vapor pressure polarization coefficient (ψ) both increase with the thickness of the ENMs, whereas the concentration polarization coefficient (β) decreases indicating the dominant effect of the temperature polarization effect. β was found to be higher for the ENMs having higher permeate fluxes and for greater feed temperatures, whereas it decreases slightly with the increase of the feed salt concentration. The thermal efficiency (EE) is enhanced with the increase of the feed temperature being in all cases for all studied ENMs greater than 78.8% and the heat transfer by conduction less than 20% of the total heat transferred through the ENMs.

Rapid speciation of methylated and ethylated mercury in urine using headspace solid phase microextraction coupled to LC-ICP-MS

Solid-phase microextraction coupled to liquid chromatography-inductively coupled plasma-mass spectrometry (SPME-LC-ICP-MS) is presented as a new approach for the extraction and speciation of methylmercury (MeHg) and ethylmercury (EtHg) in a complex urine matrix. Despite the fact that urine is one of the most easily accessible sources of biological specimens for clinical testing, reports of mercury speciation methods are limited. Without any tedious sample pretreatments or derivatization procedures, headspace SPME offers a clean and convenient one-step extraction followed by direct desorption into HPLC. In this work, the fibre was first exposed to the sample headspace for a 45 min extraction, followed by a 5 min desorption. Experimental parameters including extraction time and temperature, sodium chloride salt concentration, agitation rate and desorption time were optimized to achieve detection limits down to 0.06 μg L−1 for both organomercury species. Sample recoveries in spiked urine matrix ranged from 81.7–109.5%. The accuracy of the method was further validated using a certified reference material (TORT-2) and applied in the organomercury speciation of urine samples collected from patients with suspected mercury poisoning.

Surface morphology and thickness of a multilayer film composed of strong and weak polyelectrolytes: Effect of the number of adsorbed layers, concentration and type of salts

Self-assembled multilayered films were prepared by alternate deposition of a strong cationic polyelectrolyte, poly(trimethylammonium ethyl methacrylate chloride) and a pH-dependant anionic polyelectrolyte, poly(acrylic acid). The layer-by-layer adsorption was followed in-situ by optical fixed-angle reflectometry and after drying by ellipsometry. A recently developed “substrate thickness method” was applied to calculate the adsorbed amount of polymer from the reflectometric signal. Surface film morphology was imaged before and after drying with atomic force microscopy (AFM). Influence of the number of adsorbed layers, concentration and type of salts on the multilayer growth was examined. The number of adsorbed layers produced a specific effect on the reflectometric signal which is linked to the refractive index of the film. Adjustment of the adsorbed amount of polyelectrolytes was done by changing sodium chloride salt concentration within a range of 10 − 3 to 10 − 1 M. AFM observations showed a significant evolution in surface morphology and a maximum of surface roughness for films built-up at 10 − 2 M. Experiments were then carried out at 10 − 3 M in either barium chloride or zinc chloride salts. In the presence of Ba 2+ and Zn 2+ ions, adsorption of 5 bilayers is completely modified and the surface morphology was smoother than the multilayers obtained using sodium chloride salt.

Chromatographic Framework to Determine the Enantiomer Binding Mechanism on Pepsin Protein Surface

This paper describes sodium chloride salt effects on both dansyl-D,L aminoacid derivatives-pepsin protein surface association and the selectivity process. The thermodynamic functions of this enantiomer association were determined. The variation plots of the enantiomer association data versus the sodium chloride salt concentration (x) in the bulk solvent indicated a change in both the enantiomer-pepsin association and selectivity mechanisms. Enthalpy-entropy compensation confirmed this observation. This study shows the importance of taking into account, the electrostatic interactions and the hydrophobic effect in order to determinate optimum conditions for enantiomeric separation in this chromatographic system.

Self-Preservation of the Drop Size Distribution Function and Variation in the Stability Ratio for Rapid Coalescence of a Polydisperse Emulsion in a Simple Shear Field

Coalescence of oil-in-water emulsion droplets in a simple shear flow produced by a Couette device is considered. A phase Doppler anemometer was used to measure the droplet size distribution as a function of time for shear rates ranging from 55 to 213 s−1and for sodium chloride salt concentrations from 0.095 to 0.6 M. The initial droplet size distribution was log-normal. During the coalescence process, the size distribution was self-preserving in accordance with D. L. Swift and S. K. Friedlander's analysis [J. Colloid Sci.19,621 (1964)]. In the limiting case of negligible repulsive force due to the electric double layer, the calculated stability ratios, corrected for droplet polydispersity, agree well with the theoretical analyses of G. R. Zeichner and W. R. Schowalter [AIChE J.23,243 (1977)] and D. L. Feke and W. R. Schowalter [J. Fluid Mech.133,17 (1983)] for the case of solid particle aggregation. The good agreement between the stability ratios for the case of coalescence of droplets in the present study and those for aggregation of solid particles indicates that resistance to film deformation and thinning present in the case of coalescence is not important compared with the collision process.