Effect Of Chloride Ion Concentration Research Articles

Effects of chloride ion concentration on porous surfaces and boiling heat transfer performance of porous surfaces

Porous surfaces are a common modified surface used to enhance boiling heat transfer. In this paper, a method for preparing gradient porous surfaces is presented, that is, magnetic stirring is added to the electrolyte and the cathode surface to be deposited is placed vertically downward. Within the Cl ion concentration range of 30–140 mg/L, increasing the Cl ion concentration results in lager pore sizes. When the Cl concentration was greater than 120 mg/L, the average pore size of the surface gradually increased from the center to the edge, and the number of pores gradually decreased from the center to the edge. All surfaces showed superhydrophilicity. The critical heat flux of Sample#3 is 158.72 W/cm2, which is 67% higher than the smooth surface. The wall superheat of Sample#3 was only 15 °C in the critical state. This porous surface has plenty of nucleation sites. These nucleation sites are gradually activated when the heat flux increases. At low heat fluxes, heat transfer on these porous surfaces presents a disadvantage because the nucleation sites are not fully activated. At high heat fluxes, these porous surfaces show a decrease in wall temperature. Consequently, the porous surface prepared in this paper has good boiling heat transfer at high heat flux.

Electrochemical migration behavior between Cu and Ag under a thin electrolyte layer containing chloride

PurposeThe purpose of this paper is to investigate the effects of chloride ion concentration and applied bias voltage on the electrochemical migration (ECM) behavior between Cu and Ag under an NaCl thin electrolyte layer (TEL).Design/methodology/approachA self-made experimental setup for the ECM behavior between Cu and Ag was designed. An HD video measurement microscopy was used to observe the typical dendrite/corrosion morphology and pH distribution. Short-circuit time (SCT), short-circuit current density and the influence of the galvanic effect between Cu and Ag on their ECM behavior were studied by electrochemical tests. The surface morphology and composition of dendrite were characterized by FESEM/EDS.FindingsThe SCT increased with increasing NaCl concentration but decreased with increasing applied bias voltage, and the SCT between Cu and Ag was less than that between Cu and Cu because their galvanic effect accelerated the dissolution and migration of Cu. When NaCl concentration was less than or equal to 6 mmol/L, cedar-like dendrite was formed, whereas no dendrite formed and only precipitation occurred at high chloride ion concentration (100 mmol/L). The composition of the dendrite between Cu and Ag was copper.Research limitations/implicationsThe significance of this study is to clarify the ECM failure mechanism of printed circuit board (PCB) with an immersion silver surface finish (PCB-ImAg).Practical implicationsThis study provides a basic theoretical basis for the selection of protective measures and metal coatings for PCB.Social implicationsThe social implication of this study is to predict the service life of PCB.Originality/valueThe ECM behavior of dissimilar metals under a TEL was investigated, the influence of the galvanic effect between them on their ECM was discussed, and the SCT increased with increasing NaCl concentration.

Does winter application of road salt affect zooplankton communities in urban ponds?

Road salt (NaCl) is commonly used as a deicer during winter to improve road safety, resulting in freshwater salinization. Such elevated chloride concentrations may have a strong effect on zooplankton, which are key elements in freshwater food webs. The aim of this study was to investigate the effect of chloride ion concentration and inter-pond environmental variability on zooplankton density in four urban ponds over 3 years differing in winter conditions. Analysis of variance showed significant differences in chloride ion concentration and zooplankton density regarding study year and ponds. Redundancy analysis of column water data showed that both the environmental variables (including chloride ion concentration) and the pond location significantly contributed to the model explaining the variability in zooplankton densities. However, the environment variable (referring to the environmental variables) had a smaller contribution (11%) than the POND variable (related to the spatial configuration of the ponds), which contributed 62%, indicating that the dynamics of zooplankton density depended primarily on ecosystem characteristics. Even so, although chloride content was not the main determinant of zooplankton density, their presence in aquatic ecosystems and potential interactions with other types of pollutants could have negative biological and ecological effects.

Study on effect of chloride and temperature on corrosion behavior of CoCrFeMnNi high entropy alloy

The effect of chloride ion concentration and solution temperature on the corrosion behavior of CoCrFeMnNi high entropy alloy (HEA) was studied by electrochemical measurements, atomic force microscope (AFM) and immersion test. The result shows that increasing [Cl-]/[OH-] ratio or solution temperature enhances the electrochemical reaction ability, weakens the protection of passive film, and generates more severe pitting corrosion. The negative impact of temperature on the corrosion behavior of the HEA is more obvious than that of chloride concentration. A synergistic effect is produced between solution temperature and chloride ion concentration, which significantly destructs the denseness of passive film, and greatly decreases the anti-corrosion properties of the HEA. The pits occurred on the HEA could be ascribed to the selective dissolution of Fe, Co and Ni elements.

An efficient method for separation of Ni(II) and Co(II) with novel extractant NNPA: Synthesis, characterization, extraction behaviors, crystal structures and DFT computational studies

As the production and consumption of lithium-ion batteries increase, high purity Ni(II) and Co(II) products are becoming increasingly critical as key raw materials for battery cathodes. However, the clean and efficient separation of Ni(II) and Co(II) has been a bottleneck problem since they often coexist in ores and secondary resources and have similar ionic radii, oxidation states, and coordination numbers. Thus, this paper proposes a novel extractant (NNPA) and a breakthrough method to separate Ni(II) and Co(II). The effects of chloride ion concentration, pH value, temperature, O/A ratio and extraction time on extractant selectivity and extraction efficiency were investigated. Under optimum conditions, NNPA demonstrated high extraction ability (E = 94.6 %) and selectivity (βNi(II)/Co(II) = 481) for Ni(II) at pH 0, whereas at pH 6, it has high extraction ability (E = 93.9 %) and selectivity (βCo(II)/Ni(II) = 510.88) for Co(II). To provide in-depth insights into the Ni(II) and Co(II) separation mechanism, based on the single crystal XRD analyses of the extracted Ni(II) complex and the extracted Co(II) complex, DFT calculations were performed. The results show that the extraction order of NNPA is NNPANiHCl3 > NNPACoCl2 > NNPANiCl2(H2O)2. Due to the different selectivity of NNPA towards Ni(II) or Co(II) at different pH values, it is able to greatly reduce the consumption of extractant and significantly shorten the extraction process flow by selectively extracting the low concentration Ni(II) or Co(II) from Ni(II)-Co(II) solutions, thereby improving efficiency, reducing energy consumption and achieving cleaning production.

Electrochemical investigation on the effect of chloride ion concentration on the corrosion of concrete reinforcement using in-situ nano-Ag/AgCl electrode

In this paper, the reinforcement embedded in concrete is taken as the research object. By measuring the corrosion rate of the reinforcement in concrete, the open circuit potential of the primary battery composed of reinforcement and calomel electrode in concrete is measured. The chloride ion concentration on the surface of reinforced concrete was measured in situ by the nano-Ag/AgCl electrode. The chloride diffusion theory and corrosion electrochemistry theory were used to study the corrosion mechanism of reinforced concrete specimens. The corrosion rate of reinforced concrete increases with the increase of time in the initial stage of corrosion and reached maximum after 15 h. The pitting of concrete reinforcement is positively related to the concentration of chloride ion in the environment.

Liquid-liquid extraction of zirconium(IV) from sulphuric acid medium using a binary mixture of tri-n-octylamine and Cyanex923 in kerosene

The extraction behaviour of zirconium(IV) from sulfuric acid medium has been studied with a binary mixture of tri-n-octyl amine (TOA) and Cyanex923 (a mixture of four trialkyl phosphine oxides) in kerosene using a novel liquid-liquid extraction method. Quantitative extraction of zirconium(IV) with binary mixture of Cyanex923 and TOA in kerosene was studied by changing different parameters such as acid variation, extractant variation, effect of chloride ion concentration, effect of temperature, metal concentration variation, diluent effect, and pH effect. The percentage of extraction of zirconium(IV) decreased when the concentration of Cyanex923 and TOA increased. The percentage of zirconium(IV) was observed as 97.56% in a binary mixture of 0.007 M Cyanex923 and 0.06 M TOA. Kerosene was found to be an effective diluent for the extraction of zirconium(IV) with 97.56% extraction using a binary mixture of Cyanex923 and TOA. In addition, the stripping of the zirconium(IV) metal ion in the organic phase was also examined.

Effect of chloride ion concentration on stress corrosion cracking and electrochemical corrosion of high manganese steel

Abstract The effect of Cl− concentration on stress corrosion cracking (SCC) susceptibility of high manganese steel was investigated by slow strain rate tensile (SSRT) test, electrochemical test, and immersion test in different NaCl concentration solutions. The results show that the SCC susceptibility of the test steel first increases and then decreases with the increase in Cl− concentration. When the NaCl concentration was 10.5%, the SCC susceptibility was the highest, and the fracture showed river-like transgranular quasi-cleavage morphology, obvious tearing ridge, and strong brittle fracture characteristics. The corrosion current density of the sample first increases and then decreases with the increase in Cl− concentration in the corrosive medium. The corrosion electrochemical reaction and corrosion product layer play a synergistic role in SCC in low concentration Cl− medium. The enrichment of alloying element compounds in the corrosion layer leads to the local acidification below the corrosion layer, which promotes the anodic dissolution (AD) and forms pitting corrosion on the substrate surface. When the Cl− concentration is high, the local AD and hydrogen embrittlement (HE) caused by the dissolved oxygen will be weakened, and SCC susceptibility is reduced.

Effect of Chloride Ion Concentration on the Corrosion Behavior of 304 Stainless Steel Used in the Electric Water Heater

Effect of Chloride Ion Concentration on the Corrosion Behavior of 304 Stainless Steel Used in the Electric Water Heater

Effect of chloride ion concentration on corrosion process of selective laser melted AlSi10Mg with different heat treatments studied by electrochemical noise

The effect of chloride ion concentration on corrosion behavior of selective laser melted (SLMed) AlSi10Mg with different heat treatment (300 °C and 400 °C) was in-situ investigated by electrochemical noise (EN) technique and corrosion morphology observation. The EN signals were analyzed by noise resistance (Rn) analysis, wavelet analysis and recurrence quantification analysis (RQA). It was found that the corrosion rates of as-building and heat treated at 300 °C samples are close at the corrosion early stage when exposed to 0.1 M NaCl, while the corrosion resistance of the sample heat treated at 300 °C is lower than that of as-building sample during the whole test period when exposed to 1 M NaCl. Corrosion resistance of the sample heat treated at 400 °C is lowest in the two NaCl solutions. The relationship between the microstructures and the corrosion mechanisms is discussed. The main contribution of present study is to provide an alternative EN technique to in-situ study the corrosion behavior of SLMed AlSi10Mg and obtain some useful information, which is different from that obtained by traditional polarization curve and electrochemical impedance spectroscopy.

The Effects of Chloride Ion Concentration on the Pitting Behavior of 309L Cladding by Using Micro-Electrochemical Measurement and In Situ Optical Observation

The Effects of Chloride Ion Concentration on the Pitting Behavior of 309L Cladding by Using Micro-Electrochemical Measurement and In Situ Optical Observation

Effect of chloride Ion concentrations on luminescence peak blue shift of light-emitting diode using anti-solvent extraction of quasi-two-dimensional perovskite

In recent years, Perovskite Light-Emitting Diodes (PeLEDs) have received considerable attention in academia. However, with the development of PeLEDs, commercial applications of full-color PeLED technology are largely limited by the progress of blue-emitting devices, due to the uncontrollably accurate composition, unstable properties, and low luminance. In this article, we add Cesium chloride (CsCl) to the quasi-two-dimensional (quasi-2D) perovskite precursor solution and achieve the relatively blue shifts of PeLED emission peak by introducing chloride ions for photoluminescence (PL) and electroluminescence (EL). We also found that the introduction of chlorine ions can make quasi-2D perovskite films thinner with smoother surface of 0.408 nm. It is interesting that the EL peaks and intensities of PeLED are adjustable under different driving voltages in high concentration chlorine-added perovskite devices, and different processes of photo-excited, photo-quenched, and photo-excited occur sequentially with the increasing driving voltage. Our work provides a path for demonstrating full-color screens in the future.

Adsorption and corrosion inhibition characteristics of 2–(chloromethyl)benzimidazole for C1018 carbon steel in a typical sweet corrosion environment: Effect of chloride ion concentration and temperature

Benzimidazole derivatives are emerging as promising corrosion inhibitors for oil and gas application because they exhibit high efficiency and very good environmental profile. Although long alkyl and phenyl chains enhance their efficiency, they also increase their toxicity. Finding benzimidazole derivatives devoid of long hydrocarbon chains and with lower toxicity has become a priority. 2–(chloromethyl)benzimidazole (CMB), with log Po/w = 2.2, has been investigated as a promising low-toxic sweet corrosion inhibitor for C1018 carbon steel in CO2–saturated NaCl solution under static condition using experimental and theoretical approaches. At 25 °C, Open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) techniques confirm that CMB is an anodic-type sweet corrosion inhibitor which is able to form a protective layer on the steel surface and provide inhibition efficiency of 97.54% at 10 ppm. The efficiency increased to 98.40% and 98.58% upon increasing the temperature to 40 °C and 60 °C, respectively but decreased to 96.32% and 94.76% as the salt concentration was raised to 5.0% and 7.0% NaCl, respectively. The latter was attributed to the antagonistic competition between Cl– ions and CMB for anodic adsorption. The CMB–steel interaction is facilitated by the free electrons around N heteroatoms and C = C bonds, based on FTIR analysis and computational calculations. This eventually ameliorates the surface degradation of the steel during the sweet corrosion at 25 and 60 °C. CMB performance is highly comparable with reported sweet corrosion inhibitors with higher toxicity values.

Optimum temperature and chlorine ion concentration for hydrogen peroxide treatment of titanium dental implant material

Hydrogen peroxide treatment is a cost-effective and simple method to improve the bioactivity of titanium implants. In this study, the effects of chloride ion concentration and temperature of hydrogen peroxide on the surface treatment of titanium were investigated using X-ray diffractometry (XRD), Field Emission-Scanning Electron Microscopy (FESEM), and tests in order to determine wettability and apatite forming ability. The results showed that at the lower temperatures of treatment (60 °C), hydrogen peroxide corroded the formed titania layer and the post-heat treatment resulted in rutile formation on the surface of titanium. At higher temperatures of treatment (100 °C), a uniform and crack-free anatase layer was formed on the surface of titanium, leading to the improvement of superhydrophilicity and the apatite forming ability of titanium. However, these properties were affected by increasing the chloride concentration of hydrogen peroxide. At appropriate conditions, titanium dental implant surfaces could be treated effectively using hydrogen peroxide, such that the time of treatment could be reduced to 5 h.

Analysis of wellbore diameter variation in salt-gypsum formation with the effect of drilling fluid

Salt-gypsum rock in Eastern Sichuan Basin is widely developed; however, the creep and dissolution of salt-gypsum rock easily lead to reduced diameter or enlargement of wellbore during drilling process. This phenomenon seriously hinders the safety and efficiency of oil and gas development. In this paper, based on the dissolution test of salt-gypsum rock under the water-based drilling fluid, the salt-gypsum rock dissolution law with the effects of chloride ion concentration and temperature is studied explicitly. By incorporating the creep and dissolution effects of the salt-gypsum rock under drilling fluid, the plate of diameter reduction curve for the salt-gypsum formation is established, and the effects of the Chloride ion concentration and temperature on the reduction rate of wellbore diameter are analyzed. This research demonstrates that, under the dual actions of salt-gypsum rock dissolution and creep, as the chloride ion concentration becomes smaller and the formation temperature is lower, the diameter reduction of salt-gypsum formation turns out to be smaller. In the meanwhile, the safe drilling fluid density can be effectively reduced by optimizing the chloride ion concentration to achieve the low-density drilling, especially for the formation with lower temperature. Furthermore, a novel approach for the design of drilling fluid density in salt-gypsum formation is put forward, which provides a necessary and reliable reference for drilling operation.

Adsorption of Pd(II) onto Zr(IV) Based Metal-Organic Framework UIO-66-NH<sub>2</sub> from Hydrochloric Acid Solution

Metal-organic frameworks are used in many applications, such as gas separation, catalysis, and the synthesis of nanomaterials. Metal-organic frameworks show superior stability at high temperature, which makes them potentially useful for the adsorption of metal ions from leaching solutions at high temperature. In this work, UIO-66-NH2, a zirconium(IV) based metal-organic framework, was employed for the adsorption of Pd(II) from hydrochloric acid solutions. The adsorption percentage of Pd(II) decreased rapidly as HCl concentration increased from 0.2 M to 1 M and was negligible beyond 3 M. It was found that some of the UIO-66-NH2 was disrupted in the strong HCl solution and released Zr(IV) into the solution. The effect of chloride ion concentration on the adsorption of Pd(II) was investigated. The adsorption percentage of Pd(II) by UIO-66-NH2 decreased rapidly as chloride ion concentration increased. The adsorption of Pd(II) onto UIO-66-NH2 followed the Langmuir isotherm and reached equilibrium within 2 hours under these experimental conditions. The kinetic data for the adsorption of Pd(II) onto UIO-66-NH2 agreed well with a pseudo-second order kinetic model. The initial rate constant at 0.2 M HCl was 15.2 mg/g·min and decreased to 2.7 mg/g·min at 1.0 M HCl. More work is necessary to improve the stability of UIO-66-NH2 in strong HCl solution and to make the metalorganic framework at lower cost. Key words: metal-organic framework, palladium(II), HCl, adsorption

Effect of Chloride Ion Concentration on Corrosion of Q235 Steel in Sulfate-Reducing Bacteria Containing Solution

Effect of Chloride Ion Concentration on Corrosion of Q235 Steel in Sulfate-Reducing Bacteria Containing Solution

A support vector machine‐based ensemble algorithm for pitting corrosion modeling of EN 1.4404 stainless steel in sodium chloride solutions

The resistance to localized corrosion of stainless steel in sodium chloride solutions is evaluated at different conditions. The effects of chloride ion concentration, acidity, and temperature on pitting corrosion resistance are analyzed. In order to develop a model capable of predicting pitting corrosion behavior of EN 1.4404 by an automatic way, a support vector machine‐based ensemble algorithm is proposed. An additional step related to feature selection is included in the model in order to improve the prediction capability. According to the excellent prediction results, the support vector machines (SVM) model is used to perform a sensitivity analysis for the purpose of analyzing the influence of the environmental variables on the breakdown potential and the pitting corrosion status modeling of this grade of stainless steel. Based on this analysis, it can be concluded that the breakdown potential is the main variable to be considered in pitting corrosion modeling whereas temperature is the most important one for breakdown potential modeling.

Influence of Chloride for SCC Susceptibility on 15Cr Stainless Steel at High Temperatures under CO<sub>2</sub> Environment

The effects of chloride ion concentration on SCC susceptibility of 15Cr and 13Cr martensitic stainless steels were investigated at 180°C by SSRT. Transgranular SCC occurred in the environment containing CO2 and chloride ion. The increasing chloride ion concentration was significantly affected SCC susceptibility of 15Cr SS. In addition, the contribution of hydrogen to SCC was examined at high temperature by SSRT with electrochemically polarization. The cathodically charged specimens showed hydrogen embrittlement. The fracture surface was similar to that of high temperature SCC. On the other hand, the SCC was accelerated by anodic polarization and not by cathodic polarization. The SCC behavior of martensitic stainless steel at high temperature is affect by evolved hydrogen atom. It is concluded that hydrogen plays a key role in the crack propagation.

Potentiometric and Speciation Studies on the Complex Formation Reactions of [Pd(2-methylaminomethyl)-pyridine)(H2O)2]2+ with Some Bio-active Ligands and Displacement Reaction of Coordinated Inosine

The stoichiometry and stability constants of the complexes formed between [Pd(MAMP)(H2O)2]2+ and various biologically relevant ligands containing different functional groups were investigated. The ligands used are amino acids, peptides and DNA constituents. The results show the formation of 1:1 complexes with amino acids and peptides and the corresponding deprotonated amide species. Structural effects of peptides on amide deprotonation were investigated. The purine and pyrimidine bases uracil, uridine, cytosine, inosine, inosine 5′-monophosphate (5′-IMP) and thymine form 1:1 and 1:2 complexes. The concentration distribution of the various complex species was calculated as a function of pH. The effect of chloride ion concentration on the formation constant of CBDCA with Pd(MAMP)2+ was also reported. The results show ring opening of CBDCA and monodentate complexation of the DNA constituent with the formation of [Pd(MAMP)(CBDCA-O)DNA], where (CBDCA-O) represents cyclobutane dicarboxylate coordinated by one carboxylate oxygen. The equilibrium constant of the displacement reaction of coordinated inosine, as a typical DNA constituent, by SMC and/or methionine was calculated. The results are expected to contribute to the chemistry of antitumor agents. The calculated parameters of the optimized complexes support the measured formation constants.