The Effect of Some Anions and Cations Upon the Fluxes and Net Uptake of Chloride in the Larva of Aedes Aegypti(L.), and the Nature of the Uptake Mechanisms for Sodium and Chloride

1967 ◽  
Vol 47 (1) ◽  
pp. 35-57 ◽  
Author(s):  
R. H. STOBBART
Keyword(s):  
Chloride Concentration ◽  
Chloride Ions ◽  
Chloride Flux ◽  
Inner Surface ◽  
Net Uptake ◽  
Anions And Cations ◽  
Electron Microscopical ◽  
Anal Papillae ◽  
Uptake Mechanisms ◽  
Aquatic Larva

1. The anal papillae of the aquatic larva of Aëdes aegypti are responsible for 90% of the steady-state exchange of chloride. 2. The relationships between chloride flux and external chloride concentration are approximately described by the Michaelis equation. 3. There is net uptake of chloride, independent of uptake of sodium, from KCl, CaCl2 and NH4Cl, probably in exchange for OH' or HCO'3, but the rate is much slower than from NaCl. The following ions stimulate influx of chloride from 0.1 mM/l. KCl: H+ = Na+ < K+ The following ions inhibit it: OH' > HCO'3 > NO'3. 4. Movements of sodium and chloride ions are explicable in terms of an anionic and a cationic carrier located in an osmotic barrier in the papillae, the carriers being functionally coupled to sodium and chloride pumps located at the inner surface of the barrier. 5. An attempt is made to relate these findings to recent electron microscopical studies of the papillae.

scholarly journals Application of Novel Machine Learning Techniques for Predicting the Surface Chloride Concentration in Concrete Containing Waste Material

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2297
Author(s):  
Ayaz Ahmad ◽  
Furqan Farooq ◽  
Krzysztof Adam Ostrowski ◽  
Klaudia Śliwa-Wieczorek ◽  
Slawomir Czarnecki
Keyword(s):  
Machine Learning ◽  
Mean Square Error ◽  
Gene Expression Programming ◽  
Chloride Concentration ◽  
Absolute Error ◽  
Chloride Ions ◽  
Machine Learning Techniques ◽  
Extensive Literature ◽  
Mean Square ◽  
Chloride Concentrations

Structures located on the coast are subjected to the long-term influence of chloride ions, which cause the corrosion of steel reinforcements in concrete elements. This corrosion severely affects the performance of the elements and may shorten the lifespan of an entire structure. Even though experimental activities in laboratories might be a solution, they may also be problematic due to time and costs. Thus, the application of individual machine learning (ML) techniques has been investigated to predict surface chloride concentrations (Cc) in marine structures. For this purpose, the values of Cc in tidal, splash, and submerged zones were collected from an extensive literature survey and incorporated into the article. Gene expression programming (GEP), the decision tree (DT), and an artificial neural network (ANN) were used to predict the surface chloride concentrations, and the most accurate algorithm was then selected. The GEP model was the most accurate when compared to ANN and DT, which was confirmed by the high accuracy level of the K-fold cross-validation and linear correlation coefficient (R2), mean absolute error (MAE), mean square error (MSE), and root mean square error (RMSE) parameters. As is shown in the article, the proposed method is an effective and accurate way to predict the surface chloride concentration without the inconveniences of laboratory tests.

Chloride Regulation at Low Salinities by Nereis Diversicolor (Annelida, Polychaeta)

1970 ◽  
Vol 53 (1) ◽  
pp. 75-92
Author(s):  
RALPH I. SMITH
Keyword(s):  
Electrical Potential ◽  
Urine Volume ◽  
Chloride Concentration ◽  
Pond Water ◽  
The Body ◽  
Salinity Range ◽  
Concentration Gradients ◽  
North Eastern ◽  
Net Uptake ◽  
Chloride Regulation

1. N. diversicolor from estuarine conditions in north-eastern England can be adapted to a chloride concentration in a pond water (PW) medium at least as low as 0.9 mM/l, and shows a net uptake of chloride when returned to a medium 3-10 mM/l more concentrated. But in comparable transfers after adaptation at a chloride concentration of 10 mM/l, net uptake is not measurable. 2. Net uptake of chloride is demonstrable in the lowest salinities, where coelomic chloride concentration drops below the regulatory plateau. Net uptake reaches 3.5 µM/g wet weight/h. 3. Chloride loss is well correlated with weight loss after adaptation in 10 mM/l, but poorly so after adaptation in PW, suggesting that the urine is very hypotonic to body fluid in PW, and isotonic (or less hypotonic) at environmental chloride concentrations of 10 mM/l or higher. 4. Uptake of chloride occurs against both electrical and chemical-concentration gradients over the lower third of the environmental salinity range, which is the range in which hyperosmotic and hyperionic regulation are most pronounced. 5. The electrical potential across the body wall is maximal in PW (17 mV, inside-negative), and decreases to zero in 50 % SW. 6. Chloride influx (as measured with 36Cl) is highest in SW, and decreases in proportion to chloride concentration down to 50-25% SW, rises to a secondary maximum in 10% SW or less, and decreases as fresh water is approached. 7. Urinary chloride loss is low, and proportional to external chloride concentration in higher salinities, maximal in the c. 10% SW range of salinities, and apparently decreases to a minimum in FW. This may be in part the consequence of recovery of chloride from an hypotonic urine, in part the consequence of a reduction in urine volume. Evidence for these last two possibilities will be given in the papers which follow.

Molecular Dynamics Study of the Interaction of C-S-H and Chloride Ions

2016 ◽  
Vol 711 ◽  
pp. 1061-1068
Author(s):  
Yang Zhou ◽  
Guo Dong Xu
Keyword(s):  
Molecular Dynamics ◽  
Calcium Silicate Hydrate ◽  
Chloride Concentration ◽  
Sorption Isotherms ◽  
Hydration Product ◽  
Chloride Ions ◽  
Dynamics Modeling ◽  
Solution Interface ◽  
Molecular Dynamics Modeling ◽  
Cement Based Materials

Molecular Dynamics was employed to investigate the interaction of calcium silicate hydrate (C-S-H), the primary hydration product of cement based materials, and chloride, causing severe durable problems of concrete. The 11Å tobermorite structure was chosen to describe the C-S-H structure and the CLAYFF force field was used. It is observed in the simulation that there are no bound chlorides at 303K, while a fraction of chlorides appear in the adsorption district of tobermorite/solution interface at 323K indicating the temperature increase can improve chloride sorption capacity of C-S-H. The formation of Ca-Cl cluster is found on the surface of tobermorite, which is assumed to promote the chloride sorption. The experimental results of sorption isotherms of C-S-H in CaCl2 and NaCl aqueous solutions with the same chloride concentration have proved this point. Other researchers have made the same conclusion by means of molecular dynamics modeling, NMR tests or zeta potential experiments.

Active and passive chloride movements across isolated amphibian skin

1964 ◽  
Vol 207 (5) ◽  
pp. 1010-1014 ◽  
Author(s):  
José A. Zadunaisky ◽  
Felisa W. De Fisch
Keyword(s):  
Antidiuretic Hormone ◽  
Chloride Transport ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Chloride Ions ◽  
Amphibian Skin ◽  
Chloride Flux ◽  
Bufo Arenarum ◽  
Sodium Loss ◽  
Toad Bufo

Several aspects of chloride passage through isolated amphibian skin were studied. The chloride transport performed by the skin of the frog Leptodactylus ocellatus or the passive chloride fluxes observed in the skin of the toad Bufo arenarum Hensel are not affected by antidiuretic hormone. The chloride transport produces a negative potential and a short-circuit current in sodium-free solutions, though the unidirectional fluxes of chloride are greatly reduced under these conditions. The short-circuit current due to the chloride transport is smaller than the net chloride flux. It was found that this disagreement could be ascribed to a loss of sodium toward the inside from the sodium pool of the skin. Antidiuretic hormone did not affect the chloride current, nor the sodium loss from the skin. The isolated skin of the toad Bufo arenarum Hensel does not transport chloride ions. Thus the active transport of chloride observed in isolated skins of the frog Leptodactylus ocellatus does not depend on environmental conditions, since both animals live in the same surroundings.

scholarly journals Human sweat monitoring using polymer-based fiber

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Taekyung Lim ◽  
Youngseok Kim ◽  
Sang-Mi Jeong ◽  
Chi-Hyeong Kim ◽  
Seong-Min Kim ◽  
...  
Keyword(s):  
Sodium Chloride ◽  
Human Body ◽  
Pure Water ◽  
Body Movement ◽  
Wearable Sensors ◽  
Chloride Concentration ◽  
Chloride Ions ◽  
Coagulation Bath ◽  
Future Research ◽  
Simple Geometry

AbstractLightweight nano/microscale wearable devices that are directly attached to or worn on the human body require enhanced flexibility so that they can facilitate body movement and overall improved wearability. In the present study, a flexible poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) fiber-based sensor is proposed, which can accurately measure the amount of salt (i.e., sodium chloride) ions in sweat released from the human body or in specific solutions. This can be performed using one single strand of hair-like conducting polymer fiber. The fabrication process involves the introduction of an aqueous PEDOT:PSS solution into a sulfuric acid coagulation bath. This is a repeatable and inexpensive process for producing monolithic fibers, with a simple geometry and tunable electrical characteristics, easily woven into clothing fabrics or wristbands. The conductivity of the PEDOT:PSS fiber increases in pure water, whereas it decreases in sweat. In particular, the conductivity of a PEDOT:PSS fiber changes linearly according to the concentration of sodium chloride in liquid. The results of our study suggest the possibility of PEDOT:PSS fiber-based wearable sensors serving as the foundation of future research and development in skin-attachable next-generation healthcare devices, which can reproducibly determine the physiological condition of a human subject by measuring the sodium chloride concentration in sweat.

Aluminium corrosion studies. II. Corrosion rates in water

1977 ◽  
Vol 30 (4) ◽  
pp. 721 ◽  
Author(s):  
A Berzins ◽  
JV Evans ◽  
RT Lowson
Keyword(s):  
Corrosion Rate ◽  
Dissolved Oxygen ◽  
Chloride Concentration ◽  
Chloride Ions ◽  
Oxide Surface ◽  
Corrosion Rates ◽  
Saturated Water ◽  
Corrosion Studies ◽  
Competitive Action ◽  
Ph Range

The corrosion rate of aluminium in flowing neutral waters at 50�C has been determined as a function of pH, oxygen concentration and chloride concentration. The corrosion rate, At, as total aluminium lost between the 4th and 80th day was observed to be logarithmic according to At = B log t+C with a minimum rate in the pH range 5-6, and with B c. 3 x 10-5g cm2, C c. 20 x 10-5 g cm-2 and t in days for oxygen-saturated water. Saturating the water with nitrogen or adding up to 15 mg Cl- l-1 increased the corrosion rate. It was concluded that this was due to competitive action on the oxide surface, between dissolved oxygen and chloride ions.

Effect of severe plastic deformation by ECAP on corrosion behaviour of aluminium alloy AA 7075

2016 ◽  
Vol 81 (2) ◽  
pp. 55-61 ◽  
Author(s):  
M. Ilieva ◽  
R. Radev
Keyword(s):  
Corrosion Resistance ◽  
Aluminium Alloy ◽  
Equal Channel Angular Pressing ◽  
Pitting Corrosion ◽  
Corrosion Behaviour ◽  
Chloride Concentration ◽  
Chloride Ions ◽  
Angular Pressing ◽  
Pitting Corrosion Resistance ◽  
Aa 7075

Purpose: The present study compares the corrosion behaviour of overaged AA 7075 before and after equal channel angular pressing ECAP in two media, containing chlorides, in order to answer the question how grain refinement of aluminium alloys influences their corrosion properties.Design/methodology/approach: The effect of equal channel angular pressing ECAP on corrosion behaviour of aluminium alloy AA 7075 was studied in two water solutions, containing chloride ions: 1) 0.01 M Na2SO4 with addition of 0.01%Cl-, and 2) 3g/l H2O2 and 57g/l NaCl. The changes in electrochemical characteristics, provoked by grain size refinement after equal channel angular pressing ECAP, were found using potentiodynamic polarisation. Steady state potential, corrosion potential, corrosion current density; breakdown (pitting) potential of overaged and deformed by equal channel angular pressing ECAP aluminium alloy AA 7075 were measured.Findings: In the environment with lower chloride concentration equal channel angular pressing ECAP process led to increase in pitting corrosion resistance and in the medium with higher chloride concentration - to decrease in pitting corrosion resistance. That way grain refinement does not demonstrate a uni-directional influence on corrosion resistance of AA 70775.Research limitations/implications: The results suggest the possibility for development of materials having the same chemical composition but with different corrosion resistance to different environments.Originality/value: The paper presents the corrosion behaviour of ultrafine-grained aluminium alloy AA 7075 and the influence of the chloride ions concentration in the corrosion medium on this behaviour.

scholarly journals The chloride effect in the human embryonic haemoglobins

1995 ◽  
Vol 309 (3) ◽  
pp. 959-962 ◽  
Author(s):  
O Hofmann ◽  
G Carrucan ◽  
N Robson ◽  
T Brittain
Keyword(s):  
Oxygen Affinity ◽  
Chloride Concentration ◽  
Chloride Ion ◽  
Chloride Ions ◽  
Ion Concentration ◽  
Chloride Binding ◽  
Independent Components ◽  
Binding Data ◽  
Chloride Effect ◽  
Allosteric Model

The interactions of the three human embryonic haemoglobins with chloride ions have been investigated. Each of the three embryonic haemoglobins exhibits a unique pattern of oxygen-affinity-dependence on chloride ion concentration. Human embryonic haemoglobin Portland (zeta 2 gamma 2) is found to be completely insensitive to chloride ion concentration. Haemoglobin Gower I (zeta 2 gamma 2) shows a small concentration dependence, whilst haemoglobin Gower II (alpha 2 epsilon 2) exhibits a dependence approaching that of the adult protein. The degree of co-operativity for each protein is essentially chloride concentration independent. The chloride-dependent and -independent components of the alkaline Bohr effects have been measured for each of the embryonic haemoglobins and compared with that of the adult protein. Both the chloride-binding data and the Bohr effect have been analysed in terms of the recently developed allosteric model proposed by Perutz [Perutz, Fermi, Poyart, Pagnier and Kister (1993) J. Mol. Biol. 233, 536-545].

scholarly journals One-Step Synthesis of Green Fluorescent Carbon Dots for Chloride Detecting and for Bioimaging

2021 ◽  
Vol 9 ◽  
Author(s):  
Juan Yue ◽  
Ling Yu ◽  
Li Li ◽  
Pai Liu ◽  
Qian Mei ◽  
...  
Keyword(s):  
Carbon Dots ◽  
Limit Of Detection ◽  
Chloride Concentration ◽  
Chloride Ion ◽  
Silver Ions ◽  
Chloride Ions ◽  
Cell Functions ◽  
Green Fluorescent ◽  
Fluorescent Carbon

The chloride ion is an essential ion in organisms, which plays an important role in maintaining normal cell functions. It is involved in many cell activities, such as cell proliferation, cell excitability regulation, immune response, and volume regulation. Accurate detection of the chloride ion can balance its concentration in vivo, which is of great significance. In this study, we developed a green fluorescent carbon quantum dot to detect chloride concentration through the “off–on” mechanism. First, the fluorescence of carbon dots is quenched by the complex of sulfhydryl and silver ions on the surface of carbon dots. Then, the addition of chloride ions pulls away the silver ions and restores the fluorescence. The fluorescence recovery is linearly related to the concentration of chloride ions, and the limit of detection is 2.817 μM, which is much lower than those of other reported chloride probes. Besides, cell and zebrafish experiments confirmed the biosafety and biocompatibility of the carbon dots, which provided a possibility for further applications in bioimaging in vivo.

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