NaCl Solutions Of Different Concentrations Research Articles

Identification and Evaluation of Celery Germplasm Resources for Salt Tolerance

This study evaluated the salt tolerance in 40 celery germplasm resources to clarify the different salt tolerances of celery germplasm. A gradient treatment with different concentrations of NaCl solutions (100, 200, and 300 mmol·L−1) was used to simulate salt stress. After 15 days of salt treatment, 14 indicators related to plant growth, physiology, and biochemistry were determined. The results showed that different celery varieties responded differently to salt stress. Notably, there were significant variations in below-ground dry weight, root–crown ratio, antioxidant enzyme activity, and soluble protein content among the accessions under salt stress. Principal component analysis was used to identify important indices for evaluating salt tolerance, including plant height, spread, content of soluble protein, and so on. A comprehensive evaluation was conducted utilizing the salt damage index, principal component analysis, affiliation function analysis, and cluster analysis. The 40 celery germplasms were classified into five highly salt-tolerant, seven salt-tolerant, fifteen moderately salt-tolerant, nine salt-sensitive, and four highly salt-sensitive germplasms. SHHXQ, MXKQ, XBQC, XQ, and TGCXBQ were highly salt-tolerant germplasms, and BFMSGQ, HNXQ, ZQ, and MGXQW were highly salt-sensitive germplasms. The results of this study provide a reference for the variety of celery cultivation in saline areas and lay a foundation for the selection and breeding of salt-tolerant varieties of celery.

Effect of chloride salt migration at interfaces on asphalt-aggregate adhesion: A molecular dynamics study

Asphalt pavements can be damaged by moisture and salt, and the bond strength between asphalt and aggregate is related to the erosion of the salt solution. In this study, considering the migration and diffusion of the solution at the interface, a molecular dynamics modeling method was used to simulate the process where the salt solution erodes the asphalt-aggregate interface, and results show that the solution invades the asphalt-aggregate interface, gradually squeezing the asphalt away from the aggregate surface in a wedge shape, and the interaction force between the asphalt and the aggregate is gradually reduced to 0. The diffusion rate of the solution at the interface is related to the position of the solution. If the solution is farther away from the aggregate, it will be less restricted by the aggregate. NaCl affects the diffusion of water molecules. The greater the concentration of NaCl solution, the lower the height of the wedge formed by the solution at the interface. Compared to quartz, calcite has a stronger limiting effect on the solution, which is manifested by a greater resistance to water damage. Under the attraction of NaCl solution, the polar components are more likely to move toward the solution surface, while the less polar components show different distribution and diffusion states. In this study, we observed the conformational changes in the erosion process of different concentrations of NaCl solutions and calculated the change rule of interaction force, which helps understand the erosion process of salt solutions and provides a new idea for the study of chloride on asphalt pavement spalling.

Influence of Concentration Gradients on Electroconvection at a Cation-Exchange Membrane Surface.

Membrane-based systems, such as electrodialysis, play an important role in desalination and industrial separation processes. Electrodialysis uses alternating anion- and cation-exchange membranes with a perpendicular electric field to generate concentrated and diluate streams from a feed solution. It is known that under overlimiting current conditions, reduced charge and mass transfer at the membrane interface leads to regions of high ion depletion generating instability and vortices termed electroconvection. While electroconvective mixing is known to directly impact the separation efficiency of electrodialysis, the influence of ion concentration gradients across the membrane experienced in a functional electrodialysis system is not known. Here, we report the influence of ion concentration gradients across a cation exchange membrane (Nafion) that is both aligned with and opposed to the applied electric field. Experiments were conducted by coflowing NaCl solutions of different concentrations (0.1-100 mM) on each side of the membrane, and electroconvection was visualized with a fluorescence dye (Rhodamine 6G). We obtained concentration profiles from fluorescence image data and systematically measured the thickness of the depletion boundary layer dBL under different conditions. We found smaller dBL values at a higher flow rate both with and without concentration gradients. Our results show that electroconvection is enhanced when the electric field is opposite to the direction of the concentration gradient.

Влияние воздействий поверхностно-активных веществ на прочность образцов мерзлых вскрышных горных пород угольных месторождений криолитозоны

The harsh climatic conditions of the cryolithic zone with its long winter period and presence of permafrost soils significantly slow down all technological processes in surface mining. The resistance of frozen rocks at coal mines to digging with mining equipment can be reduced by their preliminary softening with the use of surfactants. The paper discusses the softening effect of aqueous surfactant solutions on samples of frozen overburden rocks. The authors demonstrate that treatment of rocks with solutions of optimal composition and concentration decreases their strength, which makes it possible to enhance the efficiency of In-Pit Crushing and Conveying Systems based on the rotary mechanical shovel in combination with a conveyor as well as the use of continuous miners. Experimental data are presented on the strength properties of artificially made samples of overburden rocks from the Kangalassky coal deposit saturated with surfactant solutions of different concentrations. The authors point out that the highest decrease in the samples strength is achieved when using aqueous solution of aluminum chloride. The results of experiments carried out to establish the effects of distilled water (H2O) and NaCl solutions of different concentrations on the strength properties of fine-grained sandstones from the Elga coal deposit are presented, which confirm that at the temperature of -10°С the maximum reduction of up to 55% is achieved in the strength of the samples, and when the temperature decreases from -10°С to -20°С a slight increase is observed in the sample strength. The authors suggest that the use of surfactants will reduce the strength of the frozen overburden soils, thus making it possible to apply a blast-free mining technology.

Ciprofloxacin adsorption performance of Co‐doped UiO‐66

The presence of ciprofloxacin in various water sources, even at low concentrations, causes health risks and serious environmental pollution as well as development of antibiotic resistance. So, it is critically necessary to remove ciprofloxacin effectively from the effluent. Co‐doped UiO‐66 was synthesized through one‐step hydrothermal method and evaluated as an adsorbent for ciprofloxacin adsorption. Ciprofloxacin adsorption was systematically investigated revealing adsorption isotherms, kinetics, and thermodynamics. The findings revealed that Freundlich isotherm model (maximum adsorption capacity: 45.17 mg g−1) at optimum experimental conditions (pH: 5, contact time: 90 min and adsorbent dosage: 0.3 g L−1) and acquired data were fitted using pseudo‐second‐order kinetic model. The ciprofloxacin adsorption was determined to be a spontaneous and endothermic from thermodynamic experiments. Effects of coexisting compound in the aqueous solutions on the Co‐doped UiO‐66 adsorption performance were studied using different concentrations of NaCl solution. The ciprofloxacin removal slightly decreased in the case of increasing the concentrations of Na+ ions. Regeneration of the Co‐doped UiO‐66 was carried out in methanol + acetic acid solution and repeated adsorption experiments were conducted to reveal reusability of the Co‐doped UiO‐66. Its ciprofloxacin adsorption capacity reduced to 38.0 mg g−1 after the four cycles indicating that the Co‐doped UiO‐66 was a reusable and potential adsorbent for ciprofloxacin adsorption process.

Study on the difference of high frequency dielectric properties of biological tissues measured by air and packed coaxial probe

In this paper, the differences between air probe and filled probe for measuring high-frequency dielectric properties of biological tissues are investigated based on the equivalent circuit model to provide a reference for the methodology of high-frequency measurement of biological tissue dielectric properties. Two types of probes were used to measure different concentrations of NaCl solution in the frequency band of 100 MHz-2 GHz. The results showed that the accuracy and reliability of the calculated results of the air probe were lower than that of the filled probe, especially the dielectric coefficient of the measured material, and the higher the concentration of NaCl solution, the higher the error. By laminating the probe terminal, liquid intrusion could be prevented, to a certain extent, to improve the accuracy of measurement. However, as the frequency decreased, the influence of the film on the measurement increased and the measurement accuracy decreased. The results of the study show that the air probe, despite its simple dimensional design and easy calibration, differs from the conventional equivalent circuit model in actual measurements, and the model needs to be re-corrected for actual use. The filled probe matches the equivalent circuit model better, and therefore has better measurement accuracy and reliability.

Strength and Microscopic Characteristics of Slag-Based Geopolymer-Solidified Sludge after Dry–Wet Cycling with Chloride Salt Solutions

As a new type of green soil-curing agent, geopolymers have the advantages of high strength, good durability, and low carbon emissions, and slag is widely used as a common geopolymer precursor in geopolymer production. Therefore, it is important to investigate the strength and durability of slag-based polymer-solidified sludge under the action of dry–wet cycling with chloride salt solutions. After curing the slag-based polymer-solidified sludge with NaOH (NO), Na2SiO3 (NS), and calcium carbide slag (CS) as alkali excitants to different curing ages (7, 14, 28 days), experiments involving different numbers of dry–wet cycles (0, 5, 10, 20, 30) with NaCl solutions of different concentrations (0%, 5%, 10%) were performed to investigate the unconfined compressive strength and micromorphology of the solidified sludge after undergoing dry–wet cycling. The test results showed that the strength of sludge cured with NO for 7 and 14 days showed a trend of increasing and then decreasing with an increasing number of dry–wet cycles, and the strength of sludge cured with NO for 28 days showed a trend of gradually decreasing with an increasing number of dry–wet cycles. The order of the resistance of sludge cured with the three excitants to the effect of the dry–wet cycles of chlorine salt was CS > NO > NS. After the dry–wet cycling, small cracks appeared on the surface of the NS-cured soil, the surface of the NO-cured soil was intact, and a small amount of surface peeling was observed for the CS-cured soil. Scanning electron microscopy test results showed that the chloride salt dry–wet cycles caused the formation of pores and cracks in the soil, and NaCl crystallization and Friedel’s salt production were observed in the soil, thus reducing the strength of the solidified sludge.

Synthesis of Poly (2-Acrylamido-2-methylpropanesulfnoinc Salt) Modified Carbon Spheres.

The paper reports a facile synthesis of novel anionic spherical polymer brushes which was based on grafting sodium 2-acrylamido-2-methylpropane-1-sulfonate from the surface of 4,4'-Azobis (4-cyanopentanoyl chloride)-modified carbon spheres. Various characterization methods involving a scanning electron microscope, energy dispersive X-ray spectroscopy, Fourier transform infrared spectrum, and thermo-gravimetric analysis were utilized to analyze the morphology, chemical composition, bonding structure, and thermal stability, respectively. The molecular weight (Mw) and polydispersity (Mw/Mn) of brushes were 616,000 g/mol and 1.72 determined by gel permeation chromatography experiments. Moreover, the dispersibility of ASPB in water and in the presence of aqueous NaCl solutions of different concentrations was investigated. Results show that the dispersibility of carbon spheres has been enhanced owing to grafted polyelectrolyte chains, while the zeta potential of the particle decreases and its brush layer shrinks upon exposure to sodium ions (Na+).

Moderate Salinity Stress Increases the Seedling Biomass in Oilseed Rape (Brassica napus L.).

Oilseed rape (Brassica napus L.), an important oil crop of the world, suffers various abiotic stresses including salinity stress during the growth stage. While most of the previous studies paid attention to the adverse effects of high salinity stress on plant growth and development, as well as their underlying physiological and molecular mechanisms, less attention was paid to the effects of moderate or low salinity stress. In this study, we first tested the effects of different concentrations of NaCl solution on the seedling growth performance of two oilseed rape varieties (CH336, a semi-winter type, and Bruttor, a spring type) in pot cultures. We found that moderate salt concentrations (25 and 50 mmol L-1 NaCl) can stimulate seedling growth by a significant increase (10~20%, compared to controls) in both above- and underground biomasses, as estimated at the early flowering stage. We then performed RNA-seq analyses of shoot apical meristems (SAMs) from six-leaf-aged seedlings under control (CK), low (LS, 25 mmol L-1), and high (HS, 180 mmol L-1) salinity treatments in the two varieties. The GO and KEGG enrichment analyses of differentially expressed genes (DEGs) demonstrated that such a stimulating effect on seedling growth by low salinity stress may be caused by a more efficient capacity for photosynthesis as compensation, accompanied by a reduced energy loss for the biosynthesis of secondary metabolites and redirecting of energy to biomass formation. Our study provides a new perspective on the cultivation of oilseed rape in saline regions and new insights into the molecular mechanisms of salt tolerance in Brassica crops. The candidate genes identified in this study can serve as targets for molecular breeding selection and genetic engineering toward enhancing salt tolerance in B. napus.

Study on the effective measurement area of an open-ended coaxial probe for the dielectric measurement of biological tissues.

The dielectric properties of tissues are very important physical factors for the investigation and application of bio-electromagnetism. However, the size of the active sample tissue is usually limited in actual measurement, making it difficult to meet the requirements of the existing high-frequency measurement methods, thus influencing the measurement results. The present study aimed to systematically investigate the various factors influencing the effective measurement area of the open-ended coaxial probe, including the design size of the probe and the dielectric properties of the object to be measured. The simplified material mixing model, in which several types of materials were set as the material under test (MUT) and the perfect conductor (PEC) was set as the specific material, was used in the simulation to study the effective measurement area of eight types of probes with different sizes for the dielectric measurement of different MUTs. Different concentrations of NaCl solutions and three types of coaxial probes were used in the actual measurement to verify the simulation results. According to the simulation results, the effective measurement area, especially the effective measurement radius, was closely related to the outer conductor radius of the probe. The effective measurement area of the probe decreased when the outer conductor radius of the probe reduced. Moreover, the change in the effective measurement area of the probe was independent of the MUT when the cross-sectional size of the probe was smaller than a certain threshold value. The experimental results also confirmed this conclusion. According to the research results, the independent variable dimension could be effectively reduced and the modeling difficulty was reduced when the analysis model of the effective measurement area of the probe was established.

Physiological and Biochemical Characteristics and Response Patterns of Salinity Stress Responsive Genes (SSRGs) in Wild Quinoa (Chenopodium quinoa L.)

Cultivating salt-tolerant crops is a feasible way to effectively utilize saline-alkali land and solve the problem of underutilization of saline soils. Quinoa, a protein-comprehensive cereal in the plant kingdom, is an exceptional crop in terms of salt stress tolerance level. It seems an excellent model for the exploration of salt-tolerance mechanisms and cultivation of salt-tolerant germplasms. In this study, the seeds and seedlings of the quinoa cultivar Shelly were treated with different concentrations of NaCl solution. The physiological, biochemical characteristics and agronomic traits were investigated, and the response patterns of three salt stress-responsive genes (SSRGs) in quinoa were determined by real-time PCR. The optimum level of stress tolerance of quinoa cultivar Shelly was found in the range of 250–350 mM concentration of NaCl. Salt stress significantly induced expression of superoxide dismutase (SOD), peroxidase (POD), and particularly betaine aldehyde dehydrogenase (BADH). BADH was discovered to be more sensitive to salt stress and played an important role in the salt stress tolerance of quinoa seedlings, particularly at high NaCl concentrations, as it displayed upregulation until 24 h under 100 mM salt treatment. Moreover, it showed upregulation until 12 h under 250 mM salt stress. Taken together, these results suggest that BADH played an essential role in the salt-tolerance mechanism of quinoa. Based on the expression level and prompt response induced by NaCl, we suggest that the BADH can be considered as a molecular marker for screening salt-tolerant quinoa germplasm at the early stages of crop development. Salt treatment at different plant ontogeny or at different concentrations had a significant impact on quinoa growth. Therefore, an appropriate treatment approach needs to be chosen rationally in the process of screening salt-tolerant quinoa germplasm, which is useful to the utilization of saline soils. Our study provides a fundamental information to deepen knowledge of the salt tolerance mechanism of quinoa for the development of salt-tolerant germplasm in crop breeding programs.

The Corrosion Behavior of Al-Cu-Li Alloy in NaCl Solution

Al-Cu-Li alloys are widely used in aerospace due to their excellent mechanical properties. However, the surface of Al-Cu-Li alloy components is prone to localized corrosion, when it serves in humid environments such as the ocean, due to the action of moisture in the air and Cl− in the atmosphere. Therefore, it is significant to study the corrosion performance of typical third-generation Al-Cu-Li alloys in a marine environment. The corrosion tests of the experimental materials are carried out in different concentrations of NaCl solution, and their morphology and maximum corrosion depth are characterized to evaluate their corrosion resistance at a particular time. The corrosion behavior of the third generation typical Al-Cu-Li alloys (2A97-T3, 2A97-T6, 2060-T8, and 2099-T83) and high-strength Al alloy 2024-T4 in solution containing Cl− is investigated using correlative immersion testing. The results show that 2A97-T3 possesses the best corrosion resistance performance of all under the same concentration of NaCl solution and soaking time. The corrosion resistance performance of 2024-T4 is respectively stronger than that of 2060-T8 and 2099-T83, but weaker than that of 2A97 (T3, T6). The corrosion morphologies of 2060-T8 and 2099-T83 are characterized by deep pits and large areas of exfoliation corrosion, while the corrosion morphology of 2099-T83 is the worst, indicating that its corrosion resistance is the weakest of all. The local corrosion preferentially occurred in the boundary region between intermetallic compounds or precipitates and alloy matrix in NaCl solution, and the lithium is selectively dissolved during the dissolution process, which brings about the enrichment of copper-containing residues. Subsequently, the copper-rich residue serves as the cathodic relative to the Al matrix, which leads to the anodic dissolution of the peripheral Al matrix occurs.

The Association Between Salt Taste Threshold and Hypertensive Nephropathy in Patients With Essential Hypertension

Abstract Background To investigate the relationship between salt taste threshold and hypertensive nephropathy in patients with essential hypertension. Methods A cross-sectional study was conducted in 346 hypertensive patients in Daping Hospital from 2017 to 2019. Among them 94 patients were hypertensive nephropathy and 252 hypertensive patients without renal damage served as controls. The salt taste threshold of patients was measured by taking different concentrations of NaCl solution. The difference in salt taste threshold between the 2 groups of patients was compared, and the correlation between salt taste threshold and hypertensive nephropathy was analyzed. Receiver operating characteristic (ROC) curve was used to analyze the value of salt taste threshold to predict hypertensive nephropathy. Results The salt taste threshold of the hypertensive nephropathy patients was significantly higher than that in hypertensive patients without renal damage [0.075 (0.050–0.100) vs. 0.050 (0.050–0.100) mol/l, P = 0.010]. As salt taste threshold increased, the renal function decreased gradually, which was manifested by the increase of urine microalbumin to creatinine ratio, blood creatinine, blood urea nitrogen, urine N-acetyl-β-glucosaminidase, and the decrease of estimated glomerular filtration rate. Logistic regression analysis showed that after adjusting for traditional risk factors, a higher salt taste threshold was an independent risk factor for hypertensive nephropathy (odds ratio = 1.299, 95% confidence interval [CI] 1.020–1.655, P = 0.034). The area under ROC curve was 0.586 (95% CI 0.520–0.652). Conclusions Salt taste threshold correlates with biochemical indicators of renal damage, and a higher salt taste threshold is a risk factor of hypertensive nephropathy in patients with essential hypertension.

Propagule limitation affects the response of soil methane oxidizer community to increased salinity

The extent to which propagule limitation can govern the responses of microbially-mediated processes (such as methane oxidation) to sudden environmental changes, is poorly understood. Here, we compared the ability of the methanotroph community in lakeshore soils of two lakes to respond to an experimental increase in salinity. One set of samples was taken from lakeshore soils of a freshwater lake (Yang Lake), the other from a slightly brackish lake (Qinghai Lake), both on the Tibetan Plateau. Samples were incubated in microcosms by adding ∼ 5 % 13CH4 or 12CH4 and different concentrations of NaCl solution. DNA stable-isotope probing (DNA-SIP) followed by high-throughput sequencing was used to determine how the active methanotrophic populations differed in lakeshore soils with different salinity levels. Samples from saline and freshwater lake initially showed much-reduced methane oxidation ability and methanotrophic activity at increased salinity. For the freshwater samples with the salinity of 25 to 50 g/L after NaCl addition, there was no adaptation and increase in methanotrophy after 7 days. By contrast, samples from the brackish lake showed an initial depression of methane oxidation, followed by greatly increased rates after several days. Sequencing revealed that this recovery of methanotrophy in the brackish lake samples was associated with a major switchover in composition of active methanotroph community. In particular, the relative abundance of Type Ⅰa methanotrophs became more abundant at increased salinity. It appears that in this freshwater lake environment, isolation from any nearby high-salinity-tolerant bacterial sources has prevented the possibility of full adaptation to a high salinity change in the environment, and only a moderate salinity adaptation is possible by species-sorting from within the existing community. By contrast, in the higher-salinity environment, the highly salinity-tolerant Methylomicrobium was able to break the establishment limitation in the high salinity environment and become the dominant methanotroph. Our study provides an instance of propagule limitation preventing adaptation to changed conditions.

Hydration kinetics and microstructure evolution of NaCl-mixed tricalcium silicate pastes

The hydration kinetics of tricalcium silicate (C3S) pastes mixed with different concentrations of NaCl solutions were investigated by performing isothermal calorimetry tests. At the same time, the Boundary Nucleation and Growth (BNG) model was used to analyze the calorimetry data. The model fitted well with the calorimetric results. C3S pastes mixed with NaCl solutions followed a similar reaction path to those prepared with DI water, with an accelerated reaction rate as the NaCl concentration increased. The specific parameters, such as the induction and acceleration durations, were quantified, and the relationship was established. The BNG modelling results indicated that the increasing NaCl concentration significantly increased the nucleation rate of the hydration products while decreasing their growth rate slightly. That was supported by the SEM and STEM observations. The presence of NaCl modified the morphology of the early-age calcium silicate hydrates (C-S-H) to relatively shorter and thinner fibres, which had a more compact microstructure and higher micromechanical properties than those in pure C3S pastes.

An Experimental Evaluation of Toxicity Effects of Sodium Chloride on Oviposition, Hatching and Larval Development of Aedes albopictus.

Dengue virus, one of the most important mosquito-borne viruses, has shown a sharp upward trend, spreading around the world in recent years. Control of vectors Aedes aegypti and Ae. albopictus remains crucial for blocking dengue transmission. The lethal ovitrap (LO) is one of the cost-effective traps based on the classic “lure and kill” strategy, and finding a proper long-lasting effective toxin is key to achieving the desired effect. The concentration of inorganic salts of habitat environment plays a strong role in affecting oviposition, hatching, and development of mosquitoes, but the potential insecticide activity of Sodium Chloride (NaCl) in habitat water as well as LO still lacks research. In this study, we carried out laboratory experiments to systematically explore the effects of different concentrations of NaCl solutions on oviposition, egg hatching, and larval development of Ae. albopictus. Consequently, Ae. albopictus was found to prefer freshwater to lay eggs; whereas 48.8 ± 2.6% eggs were laid in freshwater and 20% in ≥1.0% brackish water, few eggs were laid in 3.0% NaCl solution. Compared with egg hatching, larval development of Ae. albopictus presented a higher sensibility to NaCl concentration. The mortality of the 3rd–4th larvae in 1.0% NaCl solution was 83.8 ± 8.7%, while in 3.0% it reached 100%. Considering the cumulative effect of NaCl, when NaCl concentration was ≥1.0%, no eggs could successfully develop into adults. These data suggested that NaCl solutions with a concentration ≥1.0% can be used as an effective cheap insecticide for Ae. albopictus in subtropical inland aquatic habitats, and also as the “kill” toxin in LOs. Meanwhile, the concentration range from 0 to 2.0% of NaCl solution has the potential to be used as the “lure” in LOs. The technological processes of how to use NaCl as insecticide or in LOs still needs further in-depth exploration.

Shear strength of bentonite saturated with saline solutions exhibiting variety of cations

Investigation of saline solutions on the shear strength (SS) of compacted bentonite is desideratum to evaluate the safety of engineered barriers in order to safely dispose of the high-level radioactive waste. Undrained shear experiments were carried out on Na-bentonite saturated with CaCl2, KCl, and NaCl solutions. The stress-strain relationship of all the bentonite samples exhibits strain softening behavior, and the peak stress increases with the increase of the saline solution concentration. The SS of samples in saline solutions at 0.1 mol/L (M) follows the order of NaCl< KCl < CaCl2, whereas, in 0.5 M salt solutions it follows the order of NaCl<CaCl2 < KCl, indicating that the cation exchange process has a major impact on the SS of bentonite. The modified effective stress concept p’ was used to express the SS in various salt solutions based on Mohr-Coulomb criterion. The results further revealed that the solution concentration had minimal effect on the angle of internal friction φ’. In addition, the strength envelope remains the same when samples are saturated with different concentrations of NaCl solution, unlike the samples saturated with KCl and CaCl2. At lower salinity concentration (0.1 M), the SS in CaCl2 solution approaches maximum value because of higher osmotic suction. On the contrary, the SS of bentonite saturated with KCl attains the highest value at high concentration (0.5 M), which is attributed with strong K-linkage and low hydration energy of potassium ion.

Pitting Corrosion of 316 Stainless Steel Alloy in Chloride/Thiosulfate Solutions

In this study, the effect of the presence of thiosulfate ion on pitting corrosion of AISI (American iron and steel institute) 316 stainless steel alloy was investigated in four different concentrations of NaCl solutions (1, 0.1, 0.01, 0.001 M NaCl solutions). The experiments were conducted at 50 °C based on the potentiodynamic method. During the experiment, the effect of seven different thiosulfate/chloride concentration ratios were tested (zero, 0.01, 0.03, 0.075, 0.1, 0.2, and 0.3 S2O3-2/Cl-1 ratios). Pitting potential was recorded for each test. Results show that 316 stainless steel alloy has a passivity region in all tests performed. However, this passivity region was strongly affected by both the chloride concentration and the thiosulfate/chloride concentration ratio. The addition of little amount of thiosulfate to chloride solutions was found to decrease the pitting resistance of the 316 stainless steel alloy. The addition of S2O3-2 to chloride solutions resulted in a lower pitting potential value at 0.03 thiosulfate/chloride concentration ratio compared to the other ratios.

Self-/Magnetic-Propelled Catalytic Nanomotors Based on a Janus SPION@PEG-Pt/PCL Hybrid Nanoarchitecture: Single-Particle versus Collective Motions

In this paper, we synthesized superparamagnetic iron oxide nanoparticles (NPs) functionalized with (3-aminopropyl)triethoxysilane (Fe3O4@APTES). The synthesized NPs were coated with succinic anhydride (Fe3O4@COOH) in the next step. Half the surface of the NPs was shielded with wax microparticles via the Pickering emulsion technique, and the unshielded side was covered with poly(ethylene glycol) methyl ether. Platinum nanoparticles (Pt NPs) were deposited between PEG chains by the oxidation-reduction method through an in situ procedure to obtain a metal-polymer composite. These deposited Pt NPs have the potential to catalyze the decomposition of hydrogen peroxide at the surface of Janus nanomotors (JNMs). After de-waxing of the NPs, Irgacure 2959 (as the initiator) was reacted with the bare side of the NPs to provide the opportunity to grow poly(ε-caprolactone) (PCL) chains on the surface of the nanomotors through the "grafting from" method. The diffusion coefficient and velocity of the JNMs (before and after the PCL reaction) in the aqueous solution of 1, 2, 3, 5, and 10% (w/w) hydrogen peroxide and in the presence of different concentrations of NaCl solutions (0, 5, and 10% (w/v)) were investigated by mean square displacement analysis for single-particle or collective motions of JNMs. In addition, the simultaneous effect of an external magnetic field and the NaCl concentration on the movement direction of JNMs was also evaluated in the presence of hydrogen peroxide (10%). Increasing the ionic strength through NaCl addition permits the JNMs to move with relatively lower amounts of fuel [i.e., 2% (w/w)]. The collective motion investigation of the JNMs showed the highest speed in the media with 10% (w/w) hydrogen peroxide and 5% (w/v) NaCl solution (about 1215.78 μm2/s) due to the surfactant effect of the Janus architecture.

Assessing the Impact of Proline and Abscisic Acid on Salt Stress Grown BRASSICA NAPUS at Germination and Seedling Establishment

Abiotic stress such as Salinity causes serious challenge to plant growth and development, so it causes negative influence on plant's growth and yield. Different growth regulators and osmolytes kept attention as productive strategy and help the plant for enhancing stress tolerance and plant' growth and yield improved under stress condition. This project investigates the performance of Brassica napus at germination and seedling stage after application of abscisic acid and proline with combination of salt stress. Experiment was designed in completely randomized manner and petri plates were arranged in different sets with 10 seeds/each and applied with different concentrations of NaCl solutions. Proline (10 -20mM) and ABA (50-100mg/L) was pplied separately and in combination (proline 10 x ABA 50) and (proline 20 x 100) in these sets. After 8 days experiment was terminated and different parameters (germination percentage, seedling growth, shoot and root length, fresh and dry biomass, vigor index, Reletive water content, (RWC) Water content (WC), Root Shoot Ratio (RSR), Shoot Weight Ratio (SWR) and Root Weight Rratio (RWR). Salt stress exhibited significant decrease in shoot and root length, fresh and dry biomass, vigor index, RWC, different ratios (SWR, RWR) and different physiological indices while RSR exhibited increase in comparison to control in all sets. According to this research the application of proline and abscisic acid alone showed increased performance in all studied parameters. Interactions of proline and ABA did not support germination and seedling establishment process. This study concluded that application of proline (10mM) and ABA (100mg/L) improved germination and seedling establishment process very well as compared to other doses in Brasicca napus