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Journal articles on the topic 'Chloride aggression'
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1
Bataineh, H., M. H. Al-Hamood, and A. M. Elbetieha. "Assessment of aggression, sexual behavior and fertility in adult male rat following long-term ingestion of four industrial metals salts." Human & Experimental Toxicology 17, no. 10 (1998): 570–76. http://dx.doi.org/10.1177/096032719801701008.
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1 The effect of long-term ingestion of the industrial metals salts, manganese sulfate, aluminum chloride, lead acetate and copper chloride was investigated on aggression, sexual behavior and fertility in male rat. Adult male rats ingested solutions of these salts along with drinking water at a concentration of 1000 p.p.m. for 12 weeks. 2 Male rat sexual behavior was suppressed after the ingestion of manganese sulfate, aluminum chloride, lead acetate and copper chloride. The ingestion of solutions of these salts markedly prolonged the intromission and ejaculation latencies. Aluminum chloride and copper chloride reduced the copulatory efficiency. 3 Male rat aggression was also abolished after the ingestion of manganese sulfate, aluminum chloride, lead acetate and copper chloride. The ingestion of solutions of these salts markedly suppressed lateralizations, boxing bouts, fight with stud male and ventral presenting postures. 4 Fertility was reduced in male rats ingested with lead acetate. The total number of resorptions was increased in female rats impregnated by males ingested with manganese sulfate and lead acetate. 5 Body, absolute or relative testes, seminal vesicles weights were dropped in adult male rats ingested with manganese sulfate, aluminum chloride, lead acetate and copper chloride. However, the absolute or relative preputial gland weights were not affected. Collectively, these results suggest that the long-term ingestion of manganese sulfate, aluminum chloride, lead acetate and copper chloride would have adverse effects on sexual behavior, territorial aggression, fertility and the reproductive system of the adult male rat.
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Leonovich, S. N., E. E. Shalyi, and L. V. Kim. "Reinforced Concrete under the Action of Carbonization and Chloride Aggression: a Probabilistic Model for Service Life Prediction." Science & Technique 18, no. 4 (2019): 284–91. http://dx.doi.org/10.21122/2227-1031-2019-18-4-284-291.
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Reinforcement corrosion of marine and coastal hydraulic structures due to chloride aggression and concrete carbonization leads to a sharp decrease in structure safety. The reinforcement is subjected to a depassivation process as soon as a chloride concentration on its surface exceeds a certain threshold concentration, or the pH value in a concrete protective layer is decreased to a threshold value due to carbonation. Electrochemical reactions are realized with formation of corrosion products due to penetration of oxygen up to reinforcement surface. This leads to cracking of the concrete protective layer and decrease in reinforcement cross-section. The paper proposes a method for predicting a complex degradation of reinforced concrete structures with due account of various mechanisms of corrosion wear that allows to develop efficient methods for improvement of structure durability and maintainability which are operated in the marine environment. A methodology for forecasting of reinforced concrete service life prediction has been developed under a combined effect of carbonization and chloride aggression while using finite-difference and probability models. The paper takes into account initiation periods of reinforcement corrosion and propagation periods for conditions of Sakhalin shelf zone. Field surveys of Kholmsk and Korsakov port facilities are presented in the paper. Carbonization front and chloride content have been estimated according to depth of the concrete protective layer. The paper proposes a model that allows to determine an average period prior to repair while taking into account rate of concrete protective layer degradation caused by simultaneous action of two corrosion processes: carbonization and chloride aggression.
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Molodin, Vladimir Viktorovich, and Denis Sergeevich Novikov. "Features of Degradation of Reinforced Concrete Structures Subjected to Chloride Aggression." Строительное производство, no. 4 (2022): 121–27. http://dx.doi.org/10.54950/26585340_2022_4_121.
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Xu, Aoni, Chaofang Dong, Xin Wei, Xiaogang Li, and Digby D. Macdonald. "The aggression behavior study of Cl− on the defect structure of passive films on copper." RSC Advances 9, no. 28 (2019): 15772–79. http://dx.doi.org/10.1039/c9ra03402a.
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Ovchinnikov, I. I., O. V. Snezhkina, and I. G. Ovchinnikov. "Probabilistic Assessment of the Durability of Reinforced Concrete Piles under Chloride Aggression." IOP Conference Series: Materials Science and Engineering 753 (March 7, 2020): 022072. http://dx.doi.org/10.1088/1757-899x/753/2/022072.
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Czarnecki, L., and P. Woyciechowski. "Prediction of the reinforced concrete structure durability under the risk of carbonation and chloride aggression." Bulletin of the Polish Academy of Sciences: Technical Sciences 61, no. 1 (2013): 173–81. http://dx.doi.org/10.2478/bpasts-2013-0016.
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Abstract The paper presents an idea of predicting durability of concrete structures with steel reinforcement under conditions of chloride and carbonation corrosion risk. Mechanisms of destruction due to steel corrosion in such conditions are shown. The recently elaborated model of carbonation and general model of chloride diffusion have been discussed. An algorithm of the rest service life time prognosis has been shown and options of its main stages realization have been done. An example of durability prognosis for pre-stressed hollow-core floor slab with upper layer of concrete and epoxy-resin coating has been given. This example confirms the usefulness of the described prognosis method and demonstrates its helpfulness in a structure management according to the standards of EN 1504 series
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Xavier, Gustavo de Castro, Jonas Alexandre, Paulo César de Almeida Maia, et al. "Resistance to Synthetic Seawater Aggression of Clay Ceramics Incorporated with an Ornamental Stone Residue." Materials Science Forum 798-799 (June 2014): 269–74. http://dx.doi.org/10.4028/www.scientific.net/msf.798-799.269.
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Clay ceramic materials exposed to a marine environment may be subjected to complete degradation due to the presence of chloride salts in the air. The exposition allows the chloride to penetrate in structural pores causing an internal expansion, which eventually split the ceramic apart. In open air, the solar radiation as well as the rain and wind contribute to accelerate the degradation process. In the present work the laboratory assisted degradation of clay ceramics incorporated with a granite residue from ornamental stone processing was evaluated by synthetic seawater aggression according to standard procedure. The amount of incorporated residues, up to 10 wt % and the ceramic firing temperature, up to 900°C, were variable conditions statistically analyzed by factorial planning. Degradation wetting-drying tests were conducted up to 6 months. The results showed that the linear shrinkage of the residue-free ceramics do not stabilize during the test period for any firing temperature. By contrast, the residue-incorporated ceramics tend to stabilize after 4 months. In addition, a decrease in water absorption and flexural strength was observed in same speciemens.
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Shalyy, E. E., S. N. Leonovich, L. V. Kim, V. E. Rumyantseva, and N. A. Budrevich. "Probabilistic model of the combined effect of carbonization and chloride aggression on structural concrete." Вестник гражданских инженеров 15, no. 3 (2018): 123–31. http://dx.doi.org/10.23968/1999-5571-2018-15-3-123-131.
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Шалый, Евгений, Evgeniy Shalyy, Лев Ким, Lev Kim, Сергей Леонович, and Sergey Leonovich. "REINFORCED CONCRETE UNDER INFLUENCE OF CARBONIZATION AND CHLORIDE AGGRESSION: PROBABLE MODEL OF SERVICE LIFE CALCULATION." Bulletin of Belgorod State Technological University named after. V. G. Shukhov 3, no. 6 (2018): 5–14. http://dx.doi.org/10.12737/article_5b115a5ef027c2.76676320.
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Duży, Patrycja, Marta Choinska, Izabela Hager, Ouali Amiri, and Jérôme Claverie. "Mechanical Strength and Chloride Ions’ Penetration of Alkali-Activated Concretes (AAC) with Blended Precursor." Materials 15, no. 13 (2022): 4475. http://dx.doi.org/10.3390/ma15134475.
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The purpose of this study was to investigate the properties of hardened alkali-activated concrete, which is considered an eco-friendly alternative to Portland cement concrete. In this paper, the precursors for alkali-activated concrete preparations are blends of fly ash and ground-granulated blast-furnace slag in three slag proportions: 5%, 20%, and 35%, expressed as a percentage of fly ash mass. Thus, three concretes were designed and cast, denominated as AAC5, AAC20, and AAC35. Their physical and mechanical characteristics were investigated at 28 and 180 days, as well as their properties of chloride ion transport. The modified NT BUILD 492 migration test was applied to determine the chloride ions’ penetration of the alkali-activated concretes. Improvement of mechanical strength and resistance to chloride aggression was observed with ground-granulated blast-furnace slag content increase in the compositions of the tested concretes. Mercury intrusion porosimetry tests provided insight into the open pore structures of concretes. A significant decrease in the total pore volume of the concrete and a change in the nature of the pore diameter distribution due to the addition of ground granulated blast furnace slag were demonstrated.
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SHALYI, E. E., S. N. LEONOVICH, and L. V. KIM. "Degradation of Reinforced Concrete Structures of Marine Works from the Combined Impact of Carbonation and Chloride Aggression." Stroitel'nye Materialy 770, no. 5 (2019): 67–72. http://dx.doi.org/10.31659/0585-430x-2019-770-5-67-72.
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Wang, Lynn, Jeffrey Simms, Christian J. Peters, et al. "TMEM16B Calcium-Activated Chloride Channels Regulate Action Potential Firing in Lateral Septum and Aggression in Male Mice." Journal of Neuroscience 39, no. 36 (2019): 7102–17. http://dx.doi.org/10.1523/jneurosci.3137-18.2019.
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Bui Thi, Ngoc Hieu, Ngoc Anh Nguyen Thi, Gilbert Audira, et al. "Chronic Exposure to Low Concentration Lead Chloride-Induced Anxiety and Loss of Aggression and Memory in Zebrafish." International Journal of Molecular Sciences 21, no. 5 (2020): 1844. http://dx.doi.org/10.3390/ijms21051844.
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Lead and lead-derived compounds have been extensively utilized in industry, and their chronic toxicity towards aquatic animals has not been thoroughly addressed at a behavioral level. In this study, we assessed the risk of exposure to lead at a waterborne environmental concentration in adult zebrafish by behavioral and biochemical analyses. Nine tests, including three-dimension (3D) locomotion, novel tank exploration, mirror biting, predator avoidance, social interaction, shoaling, circadian rhythm locomotor activity, color preference, and a short-term memory test, were performed to assess the behavior of adult zebrafish after the exposure to 50 ppb PbCl2 for one month. The brain tissues were dissected and subjected to biochemical assays to measure the relative expression of stress biomarkers and neurotransmitters to elucidate the underlying mechanisms for behavioral alterations. The results of the behavioral tests showed that chronic exposure to lead could elevate the stress and anxiety levels characterized by elevated freezing and reduced exploratory behaviors. The chronic exposure to PbCl2 at a low concentration also induced a sharp reduction of aggressiveness and short-term memory. However, no significant change was found in predator avoidance, social interaction, shoaling, or color preference. The biochemical assays showed elevated cortisol and reduced serotonin and melatonin levels in the brain, thus, altering the behavior of the PbCl2-exposed zebrafish. In general, this study determined the potential ecotoxicity of long-term lead exposure in adult zebrafish through multiple behavioral assessments. The significant findings were that even at a low concentration, long-term exposure to lead could impair the memory and cause a decrease in the aggressiveness and exploratory activities of zebrafish, which may reduce their survival fitness.
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Zhuravel, Vitalii, Teresa Rucińska, and Olga Borziak. "Investigation of the Diffusion of Chloride Ions in Blended Cement Pastes." ce/papers 6, no. 6 (2023): 1265–68. http://dx.doi.org/10.1002/cepa.2970.
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AbstractWhen exposed to aggressive environments containing chlorides, the chlorine ion partially binds to the usual Portland cement mortar and changes its mineralogy. Chlorine ions entering the system displace sulfate from the monosulfoaluminate. Such systems form Kusel's salt at low chloride concentrations and Friedel's salt at higher concentrations. Unbound chloride ions remain dangerous for reinforcing steel, which diffuse deep into the concrete and destroy the passivating layer on the reinforcement. To assess the protective properties of concrete in relation to metal reinforcement, it is proposed to investigate the process of displacement of the diffusion front in cement composites of various compositions. It is also important to study changes in such characteristics as porosity and filtration properties, which significantly affect the penetration depth of an aggressive medium. The study of the structure, mineral and chemical composition is carried out in layers.
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Leonovich, S. N., E. E. Shaly, D. A. Litvinovsky, A. V. Stepanova, V. V. Malyuk, and A. V. Kolodey. "Reliability algorithms for calculating and predicting the durability of reinforced concrete under chloride aggression: analysis of methodology and applications." Бетон и железобетон, no. 6 (2022): 40–50. http://dx.doi.org/10.31659/0005-9889-2022-614-6-40-50.
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Miryuk, Olga. "Service properties of porous liquid glass concrete." E3S Web of Conferences 410 (2023): 01008. http://dx.doi.org/10.1051/e3sconf/202341001008.
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The article presents studies’ results of cementless lightweight concretes based on porous granular aggregate. Lightweight concrete components are specially synthesized from mixtures containing liquid sodium glass and thermal energy waste with various fineness. Thermal hardening of a matrix based on liquid glass and technogenic fillers at a temperature of 350ºС provided heat-insulating concrete with 480 kg/m3density and compressive strength of 4.7 MPa. The aim of the work is to study operational stability of lightweight concrete from genetically related components. Durability of lightweight concrete was evaluated in terms of hydro physical properties, resistance to frost and salt aggression, and cyclic heating. Methods of physical and mechanical testing of concrete have been used in the work. X-ray phase analysis and electron microscopy were used to study materials’ composition and structure. The results of complex tests showed stability of the structure of liquid glass concrete based on porous aggregate to the impact of operational factors. The lightweight concretes developed are characterized by a softening coefficient of 0.81; they withstood 50 cycles of alternating freezing and thawing, 20 cycles of cyclic exposure at a temperature of 1050ºС and 20 thermal cycles at a temperature of 250ºС; staying in aggressive sulfate and chloride magnesium solutions.
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Dacuan, Cecielle N., Virgilio Abellana, and Hana Astrid Canseco. "Mechanical Properties of Corroded-Damaged Reinforced Concrete Pile-supporting Wharves." Civil Engineering Journal 6, no. 12 (2020): 2375–96. http://dx.doi.org/10.28991/cej-2020-03091624.
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Corrosion is one of the significant deteriorations of reinforced concrete structures. It accelerated the performance loss of the structures, leading to a cross-sectional reduction of steel, which affects its mechanical properties, particularly its tensile capacity and ductility. The purpose of this study is to assess the serviceability and safety of corroded-damaged structures, particularly those exposed to aggressive marine environments. A total of 54 pcs of 150 mm-diameter and 300mm-height of cylindrical specimen were cast. Small-scaled specimens were accelerated to corrosion using impressed current techniques with a constant current density of 200 µA/cm2. Samples were immersed in a simulated environment with a 5% solution of sodium bicarbonate during corrosion acceleration. Corrosion alters the surface configuration of the steel bar. Pitting corrosions due to chloride aggression causes the residual cross-sectional area of corroded rebars to no longer round and varies considerably along its circumference and length. The reduction of the steel cross-sectional area has a significant impact on the degradation of the strength and durability of reinforcing structures. The residual capacity of the corroded reinforcement decreases with the reduction of the cross-sectional area of the steel reinforcement. The rate of corrosion affects the extent of the remaining service life of a corroded reinforced concrete structure. Doi: 10.28991/cej-2020-03091624 Full Text: PDF
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ROZENTAL, N. K., and G. V. CHEKHNII. "CHLORIDE CORROSION OF REINFORCING STEEL." Bulletin of Science and Research Center of Construction 35, no. 4 (2023): 174–85. http://dx.doi.org/10.37538/2224-9494-2022-4(35)-174-185.
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Introduction. Many years of experience in examining corrosion conditions show the dangerous adverse effects of chloride media on reinforced concrete structures.Although a large number of domestic and foreign publications have been devoted to the aggressive action of chloride salts on reinforcing steel, protection against chloride corrosion remains a relevant issue.Aim. In this work, the state of this problem, along with the methods for determining the chloride content in concrete, was assessed in order to propose the means to increase its protective action in aggressive chloride media.Materials and methods. This article discusses the following issues:– maximum permissible chloride content in concrete;– binding of chlorides by components in the matrix, the role of the mineral composition of cement;– critical evaluation of methods for determining the chloride content in concrete;– reduction of the diffusion permeability of chlorides in concrete as a method of corrosion protection.Results. The article presents the data on moisture tests of reinforced concrete prepared using Portland cement having various contents of alite, belite, and tricalcium aluminate, as well as CaCl2 additive.Indicated were the challenges of identifying aggressive free chlorides in the matrix. The need to develop a standard method for determining free chlorides in concrete was discussed. Until such a standard is developed, the chloride aggressiveness to steel in concrete can be assessed by the electrochemical method. It was shown that concretes of extremely low diffusion permeability obtained using advanced complex additives that reduce the water demand of concrete mixtures and change the charge of the matrix surface can be used as a protection measure against chloride corrosion.Presented are the results of determining the potentials of steel in concrete by electrochemical method, chlorides in concrete by colorimetric method, and diffusion permeability of chlorides in concrete.Conclusion. The corrosion activity of chlorides against reinforcing steel depends on a large number of factors, including the total chloride content and the amount of free, physically, and chemically bound chlorides.Since chloride binding depends on a large number of technological factors, it is recommended to perform electrochemical tests of reinforcing steel in concrete as per GOST 31383 to assess the hazard level of chlorides introduced into concrete with initial materials; a decision on the protective measures for reinforcing steel in chloride environments should be made on the basis of the obtained results.
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Nassima, Khial, and Rachid Mehaddene. "Using Non-Destructive Methods for the Characterization of Concrete in Aggressive Environments." International Journal of Engineering Research in Africa 15 (April 2015): 62–70. http://dx.doi.org/10.4028/www.scientific.net/jera.15.62.
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The durability of reinforced concrete structures is reduced by the chloride penetration and susceptibility of the reinforcement to chloride induced corrosion which is considered a critical physic-chemical case. As the financial impact of the phenomena is very important, it seems essential to determine it influence on strength of reinforced concrete elements subjected to aggressive environnement such us the presence of chlorides when exposed to marine environnement. As such, the determination of the ion concentrations of chlorides profile within the cement matrix is of major importance, it tool to estimate the time required by the chlorides to reach the reinforcements in sufficient quantity to depassivate the steel.
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Bogusz, Karolina, and Michał Glinicki. "Volumetric stability and elastic properties of concrete subjected to simulated service exposure conditions on road pavements." Cement Wapno Beton 27, no. 6 (2023): 410–24. http://dx.doi.org/10.32047/cwb.2022.27.6.4.
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Expressway and highway pavements are exposed to intensive impacts of exploitation, including heavy vehicle traffic and environmental factors such as temperature and moisture along with the aggression of de-icing agents. Proper selection of mineral aggregates and design of the concrete mixture composition are important for the durability of the concrete pavement. Experimental tests were conducted on concrete under simulated service exposure conditions with external exposure to a 3% sodium chloride solution. The subject of the research was the expansion and elastic properties of air-entrained concrete made with siliceous aggregates from rocks containing moderate amounts of reactive minerals. The category of reactivity of coarse aggregates was uncertain, and in the fine aggregate was moderately reactive quartz sand. Under simulated service exposure conditions on road pavements, the significant expansion of concrete specimens and a significant decrease in the resonance elastic modulus up to 12.5% were observed. The tendency of concrete to expand was related to the presence of reaction products of reactive silica in the aggregate grains with sodium and potassium hydroxides in the cement paste [ASR], confirmed by microscopic observations. Replacement of Portland cement with CEM II/A-V 42.5 N cement and CEM II/B-S 42.5 N cement significantly reduced concrete expansion and improved the stability of elastic properties. In two of the nine concrete mixtures, the selected content of siliceous fly ash and granulated blast furnace slag, 18% and 30%, respectively, turned out to be sufficient to counteract the deleterious effects of the ASR under conditions of external contact with sodium chloride solution. A practical method for predicting the durability of concrete in the conditions in which the reactivity category of the aggregate from local natural resources is uncertain was established.
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Sarasamma, Sreeja, Gilbert Audira, Stevhen Juniardi, et al. "Zinc Chloride Exposure Inhibits Brain Acetylcholine Levels, Produces Neurotoxic Signatures, and Diminishes Memory and Motor Activities in Adult Zebrafish." International Journal of Molecular Sciences 19, no. 10 (2018): 3195. http://dx.doi.org/10.3390/ijms19103195.
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In this study, we evaluated the acute (24, 48, 72, and 96 h) and chronic (21 days) adverse effects induced by low doses (0.1, 0.5, 1, and 1.5 mg/L) of zinc chloride (ZnCl2) exposure in adult zebrafish by using behavioral endpoints like three-dimensional (3D) locomotion, passive avoidance, aggression, circadian rhythm, and predator avoidance tests. Also, brain tissues were dissected and subjected to analysis of multiple parameters related to oxidative stress, antioxidant responses, superoxide dismutase (SOD), neurotoxicity, and neurotransmitters. The results showed that ZnCl2-exposed fishes displayed decreased locomotor behavior and impaired short-term memory, which caused an Alzheimer’s Disease (AD)-like syndrome. In addition, low concentrations of ZnCl2 induced amyloid beta (amyloid β) and phosphorylated Tau (p-Tau) protein levels in brains. In addition, significant induction in oxidative stress indices (reactive oxygen species (ROS) and malondialdehyde (MDA)), reduction in antioxidant defense system (glutathione (GSH), GSH peroxidase (GSH-Px) and SOD) and changes in neurotransmitters were observed at low concentrations of ZnCl2. Neurotoxic effects of ZnCl2 were observed with significant inhibition of acetylcholine (ACh) activity when the exposure dose was higher than 1 ppm. Furthermore, we found that zinc, metallothionein (MT), and cortisol levels in brain were elevated compared to the control group. A significantly negative correlation was observed between memory and acetylcholinesterase (AChE) activity. In summary, these findings revealed that exposure to ZnCl2 affected the behavior profile of zebrafish, and induced neurotoxicity which may be associated with damaged brain areas related to memory. Moreover, our ZnCl2-induced zebrafish model may have potential for AD-associated research in the future.
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Hassan, Mohd Helmi, and Norazura Muhamad Bunnori. "Study on Fluid Transport Properties between Normal Concrete Substrate and Green-USM-Reinforced Concrete (GUSMRC) Containing Ultra Fine Palm Oil Fuel Ash (U-POFA) as Repair Material." Applied Mechanics and Materials 802 (October 2015): 277–82. http://dx.doi.org/10.4028/www.scientific.net/amm.802.277.
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Corrosion of reinforcement is one of the causes of concrete deterioration by the water contained chloride ions and gas, for example hydrogen sulfide that penetrate into the concrete structures. By performing the related transport properties testing, it will fulfill the main objective of this research that is to investigate the fluid transport and bonding properties between normal concrete substrate (NC) and green USM reinforcement concrete (GUSMRC) containing ultra-fine palm oil fuel ash (UPOFA) as repair material. GUSMRC is the type of concrete that has been upgraded from the ultra-high performance fiber reinforces concrete (UHPFRC) with 50 % of UPOFA replacing the cement. Recently many researchers have found that the POFA can be used as partial cement replacement in the concrete which can improve the durability and also the fluid transportation properties. For the bonding properties, two types of surface treatment / roughness will be perform to investigate the greatest bonding and also the durability between NC substrate that act as an old structures with GUSMRC as new repair material. It’s important to perform the other related testing so that the future results obtained can be conclude either this new green ultra-high concrete can resist the harmful environmental aggression and also if it has an excellent bonding with the old concrete as a repair material.
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Wachira, Jackson Muthengia, and Joseph Mwiti Marangu. "Chloride Diffusivity in Blended Cement Made from Selected Industrial and Agrowastes." Advances in Materials Science and Engineering 2019 (June 16, 2019): 1–7. http://dx.doi.org/10.1155/2019/2814320.
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This paper reports study findings on the diffusivity of chloride ions in potential blended cement. The cement, abbreviated as PCDC, was made from blending ordinary Portland cement (OPC) with dried calcium carbide residue and an incinerated mix of rice husks, spent bleaching earth, and broken bricks. The aim of the study was to investigate the ability of PCDC to withstand aggressive chloride environment. 10 cm × 10 cm mortar cubes were prepared using PCDC and cured for 28 days in saturated calcium hydroxide solution. The cured mortar cubes were subjected to aggressive chloride media in a laboratory set up. The test cement was subjected to chloride profile analysis with depth of cover as a function of w/c ratio and curing period in alternate dry and wet environments of 3.5 percent sodium chloride solution. The experiments were carried alongside neat OPC and OPC + 25% pulverised fuel ash (OPC + 25% PFA). Results showed that PCDC exhibited lower chloride ingress as the depth of cover increased. In conclusion, the study showed that PCDC was a potential cementitious material with high ability to withstand aggressive environment of chlorides.
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Tamrazyan, Ashot G. "Life time of Reinforced Concrete floors of industrial buildings, connected with the use of chlorine." E3S Web of Conferences 535 (2024): 01012. http://dx.doi.org/10.1051/e3sconf/202453501012.
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The article deals with the issues of durability (Life time) of floors of industrial buildings associated with the presence of chlorine. It is shown that, together with carbon dioxide, chlorine forms well-soluble hygroscopic layers in the form of calcium chloride. The movement of chlorine salts causes corrosion of the reinforcement and penetrates deep into the concrete. Therefore, the service life of reinforced concrete elements when exposed to an external aggressive environment is reduced due to corrosion of reinforcement and concrete. Experimental data and analytical dependences of the advance of the front of chloride concentrations dangerous for reinforcement and destruction of concrete under the action of the considered aggressive environment are presented. A formula is derived for the design service life of reinforced concrete structures by the factor of the passivating action of the protective layer of concrete. An empirical dependence of the service life of the structure on the depth of corrosion (diameter reduction) of the reinforcement was also obtained. The coefficient of corrosive wear of reinforcement for rectangular and tee sections bending reinforced concrete elements is calculated.
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Sohawon, Haris, and Hans Beushausen. "The effect of hydrophobic (silane) treatment on concrete durability characteristics." MATEC Web of Conferences 199 (2018): 07015. http://dx.doi.org/10.1051/matecconf/201819907015.
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Hydrophobic (silane) impregnation represents a cost-effective way to increase the durability of concrete structures in cases where insufficient design cover quality and depth have been achieved. The water repellent product lines the internal capillary pore structure and provides a water-repellent concrete surface. Thus, the risk of reinforcement corrosion initiation and subsequent deterioration can be reduced as the ingress of water-dissolved aggressive species (chlorides) is minimised or prevented. The purpose of this study was to investigate the effect of silane impregnation on durability indicators, including penetrability tests and chloride ingress (bulk diffusion). The results indicate that silane impregnation reduces capillary absorption and conductivity of chloride ions. Similarly, chloride ingress in the treated concrete mixes was suppressed.
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Słomka-Słupik, Barbara, and Krzysztof Labus. "Laboratory Test and Geochemical Modeling of Cement Paste Degradation, in Contact with Ammonium Chloride Solution." Materials 15, no. 8 (2022): 2930. http://dx.doi.org/10.3390/ma15082930.
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Concrete tanks, in coke wastewater treatment plants, are exposed to aggressive wastewater with high ammonium and chloride content, deteriorating the concrete binder. Due to this, toxic compounds may migrate to the environment. The results of the experimental work presented confirmed the changes in the phase, microstructure and concentration of chlorides caused by the penetration of NH4Cl into the hardened cement paste in dry conditions. Geochemical modeling of the interactions between the aggressive solution, the cement stone matrix and the pore water was performed in order to track the destruction process effects. The results are useful for condition assessment of the structures operating under occasional immersion.
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Qiao, Jing. "A pilot study of genipin cross-linking effects on bullous keratopathy in rabbits." International Eye Research 1, no. 1 (2020): 1–6. http://dx.doi.org/10.18240/ier.2020.01.01.
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AIM: To evaluate the effects of genipin cross-linking on bullous keratopathy in rabbits. METHODS: Nine female New Zealand white rabbits with bullous keratopathy were used as an experimental model. They were randomized into three groups. Corneas in Group A (treatment group, n=3) were immersed in 0.25% genipin at 24℃ for 40min; those in Group B (control group, n=3) were immersed in 0.9% sodium chloride solution at 24℃ for 40min; and those in Group C (blank control group, n=3) received no treatment. Follow-up examinations were performed within 2wk after treatment, including slit-lamp microscopy, central corneal thickness (CCT), evaluations of body weight and stress responses, histopathological analyses, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) for detecting stromal cell apoptosis. RESULTS: Compared to Groups B and C, remission of corneal edema, corneal healing, disappearance of epithelial bullae, a significant decrease in CCT (P<0.05), and a significant increase in body weight (P<0.05) were found in Group A. Animals in Group A became more active and showed less aggression and violent resistance behavior. More regular and dense arrangement of collagen fibers in the corneal stroma and formation of blue strips of cross-linking products were observed in Group A. Cell apoptosis occasionally occurred in the corneal stroma of Group A, while no cell apoptosis was observed in Groups B and C. CONCLUSION: Genipin cross-linking treatment for bullous keratopathy in rabbits results in remission of corneal edema and relief of pain. We hypothesize that genipin cross-linking strengthens collagen fibers in corneal stroma to avoid the formation of corneal edema and bullae.
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Faizullah, Jan. "Conventional and Rubberize Concrete Cylinders Filled with PVC Tube." International Journal of Engineering Works (IJEW) 6, no. 05 (2019): 172–75. https://doi.org/10.5281/zenodo.2665711.
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The use of composite materials poly-vinyl chloride (PVC) in construction were studied. The use of PVC plastic pipe for concrete tubing is an alternative to use instead of concrete encased in steel tube and hence improve strength, ductility, durability, economical and environmental friendly. The key application of PVC tubing was its use in high aggressive environments and stop the penetration of chlorine and carbon dioxide directed towards core concrete and defect core concrete. Although the use of PVC as a composite materials in aggressive environments are efficient but PVC behave like brittle materials. The main parameters discussed are geometric and materials properties of thin PVC, stay-in-place formwork, PVC tubing from conventional concrete and rubberize concrete, confinement.
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Chambua, Safiel Tumaini, Yusufu Abeid Chande Jande, and Revocatus Lazaro Machunda. "Strength and Durability Properties of Concrete Containing Pumice and Scoria as Supplementary Cementitious Material." Advances in Materials Science and Engineering 2021 (April 23, 2021): 1–13. http://dx.doi.org/10.1155/2021/5578870.
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Concrete structures suffer serious deterioration under a corrosive environment. Consequently, the service life of these concrete structures is decreased and deteriorates under combined attack of sulphate and chlorides. Most studies confined on single deteriorating factor such as sulphate attack only or chloride attack only but the current study focused on the influence of natural pumice (NP) and natural scoria (NS) on the strength performance of concrete exposed to the combined attack of sulphate and chloride. Portland cement (PLC) was replaced with NP or NS at a substitution level of 10%. Concrete samples were cured in water for the curing period of 28 days. Afterwards, the specimens were immersed in 5% sodium sulphate (Na2SO4), 5% sodium chloride (NaCl), and combined sodium sulphate and chloride solutions for additional curing of 28, 56, and 90 days. The results were compared between concrete mixes with NP or NS and control mix (CT) with PLC. The effects of sulphate, chloride, and combined sulphate and chloride were evaluated in terms of change in weight, variation in compressive strength, and degree of damage. Conclusively, the application of NP and NS has extraordinary potential to be utilized as a cementitious material in concrete to increase the resistance against aggressive salts.
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Raczkiewicz, Wioletta, Magdalena Bacharz, Kamil Bacharz, and Michał Teodorczyk. "Reinforcement Corrosion Testing in Concrete and Fiber Reinforced Concrete Specimens Exposed to Aggressive External Factors." Materials 16, no. 3 (2023): 1174. http://dx.doi.org/10.3390/ma16031174.
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One of the leading causes of reinforced concrete degradation is chloride attack. It occurs due to the penetration of chlorides through pores and cracks into the concrete cover. This phenomenon becomes more dangerous if reinforced concrete elements are subjected to cyclic temperature changes. The concrete cover protects against corrosion. This paper presents research, the primary purpose of which was to determine the effect of the addition of steel fibers to concrete on the development of corrosion of the main reinforcement. The tests were carried out on three types of reinforced concrete specimens made of ordinary concrete and concrete with different amounts of steel fibers (0.25% and 0.50%). In order to initiate corrosion processes, specimens were partially submerged in a 3% sodium chloride solution and were subjected to freeze–thaw cycles. The electrochemical polarization galvanostatic pulse method was used for analyzing the reinforcement corrosion activity. Moreover, it was verified whether the corrosion of reinforced concrete elements affects the acoustic emission wave velocity. The addition of steel micro-reinforcement fibers increases the corrosion resistance of reinforced concrete. In addition, a strong linear correlation between the AE wave velocity and the values of the corrosion current density was revealed.
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Benea, Lidia, and Nicoleta Simionescu. "Effect of Biological Solution and pH on Corrosion Resistance of 304L SS for Dental Brackets." Revista de Chimie 71, no. 4 (2020): 180–87. http://dx.doi.org/10.37358/rc.20.4.8056.
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This study is undertaken to evaluate the accuracy of corrosion resistance of commercially available 304L stainless steel in biological solutions with different composition and pH. Electrochemical methods such as: open circuit potential (OCP), potentiodynamic polarization curves (PD), linear polarization resistance (Rp) and cyclic polarization (CV) were used for corrosion investigations. The results show different behavior during corrosion tests in the solutions with different pH, different content of chlorides and different oxidizing character. Highest instability is revealed for 304L stainless steel in Hank`s solution due to the presence of chloride aggressive ions.
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Kheswa, Banele Siyabonga, David Whitefield, Herman Potgieter, and Michael Bodunrin. "Corrosion Behaviour of S32101 (1.4162—X2CrMnNiN21-5-1) Stainless Steel in Pulping Liquors." Materials 18, no. 9 (2025): 1921. https://doi.org/10.3390/ma18091921.
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The corrosion behaviour of lean duplex S32101 (1.4162—X2CrMnNiN21-5-1) stainless steel was assessed in various corrosive environments relevant to the pulp and paper industry. Electrochemical techniques, including open-circuit potential measurements and cyclic polarisation, were used to evaluate the corrosion resistance of S32101 stainless steel in various acidic, saline, and industrial liquors such as black, green, and white liquors, as well as dissolved chlorine dioxide bleaching solutions. To evaluate the extent of damage and corrosion mechanisms, post-exposure surface analysis was conducted using scanning electron microscopy (SEM). The results showed that S32101 experienced pitting corrosion in chloride-containing solutions, particularly in salt and acidified-salt environments. Corrosion rates increased with rising temperatures across all solutions. The highest corrosion rate of 3.17 mm/yr was observed in the highly alkaline white liquor at 50 °C, whilst chlorine dioxide induced the least aggressive effects at all temperatures. The suitability of S32101 stainless steel in handling pulp and paper liquors is shown in its corrosion resistance against the bleaching medium and low-temperature saline solutions, but it is not recommended for prolonged exposure to high alkaline liquors or chloride-rich solutions.
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Nogueira, C. G., E. D. Leonel, and H. B. Coda. "Reliability algorithms applied to reinforced concrete structures durability assessment." Revista IBRACON de Estruturas e Materiais 5, no. 4 (2012): 440–50. http://dx.doi.org/10.1590/s1983-41952012000400003.
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This paper addresses the analysis of probabilistic corrosion time initiation in reinforced concrete structures exposed to ions chloride penetration. Structural durability is an important criterion which must be evaluated in every type of structure, especially when these structures are constructed in aggressive atmospheres. Considering reinforced concrete members, chloride diffusion process is widely used to evaluate the durability. Therefore, at modelling this phenomenon, corrosion of reinforcements can be better estimated and prevented. These processes begin when a threshold level of chlorides concentration is reached at the steel bars of reinforcements. Despite the robustness of several models proposed in the literature, deterministic approaches fail to predict accurately the corrosion time initiation due to the inherently randomness observed in this process. In this regard, the durability can be more realistically represented using probabilistic approaches. A probabilistic analysis of ions chloride penetration is presented in this paper. The ions chloride penetration is simulated using the Fick's second law of diffusion. This law represents the chloride diffusion process, considering time dependent effects. The probability of failure is calculated using Monte Carlo simulation and the First Order Reliability Method (FORM) with a direct coupling approach. Some examples are considered in order to study these phenomena and a simplified method is proposed to determine optimal values for concrete cover.
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Senderowski, Cezary, Wojciech Rejmer, and Piotr Bilko. "Effect of Low Chloride and Sulfate Concentrations on Corrosion Behavior of Aluminum and Zinc Arc Thermal Sprayed Coatings." Coatings 12, no. 5 (2022): 653. http://dx.doi.org/10.3390/coatings12050653.
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The aim of this study was to determine the suitability of arc sprayed zinc and aluminum coatings as materials for protective coatings of different heating systems. The most aggressive chemical agents occurring in heating water are chloride and sulfate anions. Both ions are responsible for the corrosion of metals due to their high electronegativity and standard electrochemical potential. Water in heating systems should not contain more than 150 mg/L anions, including no more than 50 mg/L of chlorides and 100 mg/L of sulfates. To determine the corrosion resistance of three types of zinc and aluminum coatings, open circuit potential and linear polarization resistance (LPR) tests were conducted in eight alkaline solutions with different sulfate and chloride contents. The SEM/EDS structural properties of sprayed coatings at specific arc process parameters were investigated. Zinc coatings exhibit the most stable corrosion potentials in varying environments but have higher corrosion current density. Aluminum coatings exhibit much higher potential values in a chloride environment than in any other. A chloride environment also causes the lowest corrosion rates for aluminum-coated samples. A small addition of aluminum to the zinc coating (15 wt.%) does not appear to affect the stability of the corrosion potential but does result in a reduction in corrosion rates in chloride solutions.
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Kappes, Mariano A. "Localized corrosion and stress corrosion cracking of stainless steels in halides other than chlorides solutions: a review." Corrosion Reviews 38, no. 1 (2020): 1–24. http://dx.doi.org/10.1515/corrrev-2019-0061.
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AbstractFluorides, bromides, and iodides, despite being less common than chlorides, are present in various environments of industrial relevance. Stainless steels suffer pitting corrosion in solutions of all halides except fluorides, which can be understood considering that fluoride is the anion of a weak acid. The aggressiveness of the rest of the halides for pitting corrosion is on the order Cl− > Br− > I− for stainless steels with Mo content below 3 wt.%. Mo is not as effective in inhibiting Br− pitting corrosion as it is for inhibiting Cl− pitting corrosion. Most of those observations were rationalized based on the effect of anions on pit growth kinetics. Sensitized austenitic stainless steel suffers stress corrosion cracking (SCC) in solutions of all halides, albeit chlorides seem to be the most aggressive. Fluoride SCC is relevant for SCC under insulation of stainless steels, and standards and regulations developed to mitigate this problem consider this ion as aggressive as chloride. For the solubilized stainless steels, aggressiveness toward SCC is in the order Cl− > Br−. The SCC of solubilized stainless steels was not observed in solutions of F− and I−, and the possible reasons for this fact are discussed.
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Al-Safi, Sulaiman, Abdulghani Altharehi, Ibrahim A. Alameri, and Abdulmalek Al-Jolahy. "The mechanical properties of cement mortar reinforced with silica fume subjected to sulfate and chloride environment." Challenge Journal of Structural Mechanics 11, no. 1 (2025): 55. https://doi.org/10.20528/cjsmec.2025.01.005.
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This study investigates the effect of incorporating micro-sized silica fume on the mechanical properties and durability of cement mortar when exposed to sulfate and chloride environments. Mortar samples were prepared by replacing cement with micro-sized silica fume in varying proportions of 5%, 10%, 15%, 20%, 25%, 30%, and 35% by weight. The specimens were cured in water and chemically aggressive conditions, including 5% and 10% sodium sulfate solutions, as well as mixtures of 5% and 10% sodium chloride solutions, to simulate real-world exposure to such environments. Experimental results revealed that the addition of silica fume significantly enhanced the mortar's resistance to chemical deterioration caused by sulfates and chlorides. This improvement is attributed to the pozzolanic reaction of silica fume, which contributed to denser microstructures, reduced porosity, and a stronger bond within the matrix. Among the tested proportions, the optimal replacement ratios for achieving the best balance between mechanical strength and durability were identified up to 20%. These findings highlight the efficiency of silica fume as a supplementary cementitious material in mitigating the adverse effects of aggressive chemical agents. Such modifications can be particularly valuable in improving the service life of concrete structures exposed to harsh environmental conditions, enhancing sustainability and cost-effectiveness in construction practices.
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Bolzoni, Fabio, Andrea Brenna, Silvia Beretta, Marco Ormellese, Maria Vittoria Diamanti, and Maria Pia Pedeferri. "Evaluation of Preventative Methods against Rebar Corrosion in Concrete." Key Engineering Materials 919 (May 11, 2022): 132–42. http://dx.doi.org/10.4028/p-9yww6l.
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Prevention of rebar corrosion is achieved in the design and construction phases, by means of suitable mix design, casting and curing, and adequate cover depth; this approach have been introduced in international standards (EN 206) and design codes (Eurocode 2). Additional protection methods (cathodic protection, stainless steel or galvanised rebars, corrosion inhibitors, concrete coatings) can be used in very aggressive environment, especially in presence of chlorides, or when increased service life is required. In this work a simplified performance-based approach, based on Monte Carlo simulation, has been used to evaluate the service life (initiation time of corrosion) in chloride containing environments. The results confirmed that cathodic prevention and stainless steels are the most effective protection methods to guarantee a safe working condition in a severe environment. The use of pozzolanic or slag cement is confirmed as an effective way to slow chloride transport and by this way to increase the service life.
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Hunting, Andrew, Sujeeva Setunge, and Daniel Kong. "The Effects of Ocean Salinity Variance due to Climate Change on Australian Seaport Infrastructure." Applied Mechanics and Materials 438-439 (October 2013): 157–65. http://dx.doi.org/10.4028/www.scientific.net/amm.438-439.157.
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As the effects of climatic change become more evident and extreme, there is significant pressure being mounted onto port authorities and infrastructure stakeholders to ensure that their assets are resilient to the effects of a more aggressive and corrosive climate. Typically, the reinforcing steel within concrete which provides its flexural strength is protected from corrosion by both the alkalinity of the cement and the distance of cover from the chloride laden environment. However, studies are suggesting that as the hydrological cycle around the equator begins to accelerate, the salinity of the oceans at these lower latitudes (namely from 25°S to 25°N) will increase. As demonstrated through Ficks 2ndLaw of diffusion, there will then be an effect on the build-up of surface chlorides and thus, chloride ingress through the cement matrix to initiate corrosion. Through an extensive literature review of climatic forecasts, and both laboratory and in-field trials, this paper will numerically demonstrate the relationship between salinity concentration and surface chloride levels at varying temperatures. The results illustrate a strong positive relationship between the two parameters suggesting faster corrosion initiation, and more frequent operational downtime for stakeholders into the future. To fill this gap in knowledge, the surface chloride equations presented should be considered when design, maintenance, and retrofitting options are being considered for stakeholders within the affected locations.
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Kozol, Robert A., and Julia E. Dallman. "Drugs prescribed for Phelan-McDermid syndrome differentially impact sensory behaviors in shank3 zebrafish models." F1000Research 12 (September 27, 2023): 84. http://dx.doi.org/10.12688/f1000research.127830.2.
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Background: Altered sensory processing is a pervasive symptom in individuals with Autism Spectrum Disorders (ASD); people with Phelan McDermid syndrome (PMS), in particular, show reduced responses to sensory stimuli. PMS is caused by deletions of the terminal end of chromosome 22 or point mutations in Shank3. People with PMS can present with an array of symptoms including ASD, epilepsy, gastrointestinal distress, and reduced responses to sensory stimuli. People with PMS are often medicated to manage behaviors like aggression and/or self-harm and/or epilepsy, and it remains unclear how these medications might impact perception/sensory processing. Here we test this using zebrafish mutant shank3ab PMS models that likewise show reduced sensory responses in a visual motor response (VMR) assay, in which increased locomotion is triggered by light to dark transitions. Methods: We screened three medications, risperidone, lithium chloride (LiCl), and carbamazepine (CBZ), prescribed to people with PMS and one drug, 2-methyl-6-(phenylethynyl) pyridine (MPEP) tested in rodent models of PMS, for their effects on a sensory-induced behavior in two zebrafish PMS models with frameshift mutations in either the N- or C- termini. To test how pharmacological treatments affect the VMR, we exposed larvae to selected drugs for 24 hours and then quantified their locomotion during four ten-minute cycles of lights on-to-off stimuli. Results: We found that risperidone partially normalized the VMR in shank3 models. LiCl and CBZ had no effect on the VMR in any of the three genotypes. MPEP reduced the VMR in wildtype (WT) to levels seen in shank3 models but caused no changes in either shank3 model. Finally, shank3 mutants showed resistance to the seizure-inducing drug pentylenetetrazol (PTZ), at a dosage that results in hyperactive swimming in WT zebrafish. Conclusions: Our work shows that the effects of drugs on sensory processing are varied in ways that can be genotype- and drug-dependent.
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Kozol, Robert A., and Julia E. Dallman. "Drugs prescribed for Phelan-McDermid syndrome differentially impact sensory behaviors in shank3 zebrafish models." F1000Research 12 (January 23, 2023): 84. http://dx.doi.org/10.12688/f1000research.127830.1.
Full textAbstract:
Background: Altered sensory processing is a pervasive symptom in individuals with Autism Spectrum Disorders (ASD); people with Phelan McDermid syndrome (PMS), in particular, show reduced responses to sensory stimuli. PMS is caused by deletions of the terminal end of chromosome 22 or point mutations in Shank3. People with PMS can present with an array of symptoms including ASD, epilepsy, gastrointestinal distress, and reduced responses to sensory stimuli. People with PMS are often medicated to manage behaviors like aggression and/or self-harm and/or epilepsy, and it remains unclear how these medications might impact perception/sensory processing. Here we test this using zebrafish mutant shank3ab PMS models that likewise show reduced sensory responses in a visual motor response (VMR) assay, in which increased locomotion is triggered by light to dark transitions. Methods: We screened three medications, risperidone, lithium chloride (LiCl), and carbamazepine (CBZ), prescribed to people with PMS and one drug, 2-methyl-6-(phenylethynyl) pyridine (MPEP) tested in rodent models of PMS, for their effects on a sensory-induced behavior in two zebrafish PMS models with frameshift mutations in either the N- or C- termini. To test how pharmacological treatments affect the VMR, we exposed larvae to selected drugs for 24 hours and then quantified their locomotion during four ten-minute cycles of lights on-to-off stimuli. Results: We found that risperidone normalized the VMR in shank3 models. LiCl and CBZ had no effect on the VMR in any of the three genotypes. MPEP reduced the VMR in wildtype (WT) to levels seen in shank3 models but caused no changes in either shank3 model. Finally, shank3 mutants showed resistance to the seizure-inducing drug pentylenetetrazol (PTZ), at a dosage that results in hyperactive swimming in WT zebrafish. Conclusions: Our work shows that the effects of drugs on sensory processing are varied in ways that can be highly genotype- and drug-dependent.
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Usman Ghani, Usman Ghani, Shah Hussain Shah Hussain, Noor ul Amin Noor ul Amin, Maria Imtiaz Maria Imtiaz, Shahid Ali Khan Shahid Ali Khan, and Muhammad Naeem Muhammad Naeem. "Chloride and Sulfate Resistance of Calcined Lateritic Clay-Based Geopolymer." Journal of the chemical society of pakistan 44, no. 2 (2022): 140. http://dx.doi.org/10.52568/000995/jcsp/44.02.2022.
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The dissemination of chloride and sulfate ions greatly affects the quality and strength of concrete obtained from cementitious materials. The current research is focused on the development of good quality geopolymer from calcined lateritic clay, sodium metasilicate, and aluminum hydroxide with optimum Si to Al ratio (by mass) and study of its resistance in aggressive environments of chloride and sulfate. Different geopolymer samples with Si to Al ratio of 3 to 1 were prepared and exposed in 8 wt.% sodium chloride and sodium sulfate solutions for 7, 14, 21, 28, and 35 days. The geopolymer sample with Si to Al ratio = 1.5 offers greater resistance in aggressive environments. The resistance of geopolymer remained better in sodium chloride solution than in sodium sulfate solution. The reduction of compressive strength of the geopolymer is 7% less in sodium chloride solution than in sodium sulphate solution. FTIR and XRD investigation proved that both chloride and sulfate do not affect the bonding and structural features of geopolymer however slight erosion of the surface morphology confirmed by SEM analysis. It can be concluded that an impure clay can be utilized to obtain a valuable product.
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Komelin, I. M., A. P. Lysenko, and D. S. Kondrat'eva. "Corrosion of carbon steel and cast iron in gas phase above salt melts used in magnesium industry." Izvestiya Vuzov Tsvetnaya Metallurgiya (Proceedings of Higher Schools Nonferrous Metallurgy, no. 1 (February 22, 2019): 34–49. http://dx.doi.org/10.17073/0021-3438-2019-1-34-49.
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Corrosion tests of SCh15 cast iron, Steel 3 and Steel 3 with aluminized coating in some compositions of 10%MgCl2-KCl-NaCl and 10%MgCl2-KCl-Naa-Caa2 salt melts with 10 %, 25 % and 40 % CaCl2 concentrations, and also in 10MgCl2-45%KCl-20%NaCl-25%NaBr melt, and in the gas phase above these melts at 700 °C. A gravimetric method was used to determine corrosion rates of metal samples. Chemical analysis of absorption solutions was used to determine concentrations of halide and hydrogen halide impurities in air blown through the reactor with melts and samples. It was shown that carbon steel aluminizing can reduce the corrosion rate in the gas phase over the salt melt by a factor of 5 to 70. The formation mechanism of gases aggressive in relation to carbon steel and cast iron in atmospheric air in contact with salt chloride melt was considered. Accelerated hydrogen chloride and chlorine formation during the salt melt interaction with atmospheric air under the influence of iron corrosion products was found.
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Huang, Ying, Jun Wei, Rong Zhen Dong, and Hui Huang Yan. "Numerical Stimulation Method of Chloride Concentration in the Concrete Structure Exposed to Chloride Aggressive Environment." Applied Mechanics and Materials 193-194 (August 2012): 466–71. http://dx.doi.org/10.4028/www.scientific.net/amm.193-194.466.
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In this paper, based on the similarity between chloride diffusion equation in concrete and heat conduction equation the thermal analysis module of the ANSYS finite element software was used to carry out the numerical simulation for chloride ion diffusion process in concrete. And the numerical results were compared with the analytical solutions of chloride diffusion equation, which showed that the method is effective for the chloride diffusion analysis. Time-dependence of chloride diffusion coefficient in concrete was considered by amending the chloride diffusion coefficient with various parameters. Finally it is a feasible method that the chloride ion concentration in concrete structures was calculated by thermal analysis module of the ANSYS.
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Falaciński, Paweł, Agnieszka Machowska, and Łukasz Szarek. "The Impact of Chloride and Sulphate Aggressiveness on the Microstructure and Phase Composition of Fly Ash-Slag Mortar." Materials 14, no. 16 (2021): 4430. http://dx.doi.org/10.3390/ma14164430.
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The article discusses the results of examining the impact of aggressive solutions on specimens of mortars with a slag-ash binder. Bar specimens were exposed to unidirectional diffusion of sodium chloride and sodium sulphate for 90 days. Next, the specimens were subjected to flexural and compressive strength tests, ion content tests, XRD phase composition tests, and microstructural SEM-EDS tests. The test results indicated that aggressive solution action resulted in decreased flexural strength, however, it did not impact the compressive strength of mortars. A minor impact of chloride ions on the pH of the pore liquid was recorded, while the tests did not show any influence of sulphate ions. Furthermore, aggressive ion concentration decreased in deeper specimen slices. Specimen phase composition testing after chloride ion action indicated the presence of a small amount of Friedel’s salt, while regular sodium chloride crystals were identified in the microscopic image. The performance properties of mortars exposed to the action of aggressive solutions were maintained.
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Lehner, Petr, Lenka Koubová, and Miroslav Rosmanit. "Study of Effect of Reference Time of Chloride Diffusion Coefficient in Numerical Modelling of Durability of Concrete." Buildings 12, no. 9 (2022): 1443. http://dx.doi.org/10.3390/buildings12091443.
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The results of numerical calculations on the resistance of the reinforced concrete bridge deck to chlorides are compared with a different approach to the diffusion coefficient of the input parameter, and presented. The aim is to point out the necessity of a correct model adjustment in the case of using diffusion parameters obtained differently at different measurement times. The diffusion parameter, as a typical concrete material constant, was derived from electrical resistivity measurements and using the least-squares method from a direct chloride test. Due to the different times of obtaining the concrete parameters, a control calculation was performed, which showed that the numerical model for calculating the initiation of reinforcement corrosion in chloride-exposed reinforced concrete requires the application of not only a suitable diffusion parameter but also an adequate reference time. The article points out the need to use an adequate reference time introduced in the numerical calculation of the durability of reinforced concrete with respect to aggressive substances. The results show that the most appropriate reference time value is derived from the average measurement time related to the lifetime of the concrete.
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Xu, Yu Ye, and Bi Lan Lin. "Corrosion Behavior of HRB400 Reinforcing Steel Using Cyclic Potentiodynamic Polarization Technique." Advanced Materials Research 250-253 (May 2011): 207–12. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.207.
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HRB400 reinforcing steel due to high strength and high ductibility is as the main reinforcing steel in “Code for design of concrete structures (GB50010-2002)” in China. Cyclic potentiodynamic polarization technique was used to investigate the electrochemical corrosion bebavior of HRB400 reinforcing steel in Simulated Concrete Pore solutions (SCP solutions) differently contaminated by bicarbonate ions and/or chloride ions. The evolution feature of the corrosion parameters was analyzed and was compared with that of HPB235 reinforcing steel. The results show that the corrosion characteristics of HRB400 and HPB235 were exceedingly similar before the destruction of the passivation film. However, HRB400 is remarkedly more susceptible to chloride ions and carbonation than HPB235 during the failure of the passivation films. The pH threshold for HRB400 is larger than that for HPB235, and the chlorides threshold for the former is smaller than that of the latter. When HRB400 and HPB235 were connected and exposed to an aggressive environment, the galvanic corrosion will occur where HRB400 is anode and HPB235 is cathode. To ensure the durability of the reinforcing concrete structures, it is necessary to make the connection points insulate.
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Subash, Smrithy, Sumedha Moharana, and Yamini Sudha Sistla. "Inhibition Mechanism of Oxalhydrazide on Reinforcing Steel in Pore Solution Contaminated by 3.5%NaCl - Experimental and Theoretical Study." MATEC Web of Conferences 378 (2023): 07005. http://dx.doi.org/10.1051/matecconf/202337807005.
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Concrete is one among the most consumed materials on the planet secondary to water. However, the degradation of concrete happens due to the corrosion of reinforcement. Although the pore solution of concrete is alkaline, the corrosion of rebars in concrete is triggered due to aggressive ions like chlorides entering the concrete. The most common method of corrosion inhibition is by utilising corrosion inhibitors which when added to the concrete stays in the pore solution and prevents the corrosion of surface of rebars from aggressive ions. Although there are number of inhibitors, the rise in corrosion deterioration demands the need for new potential inhibitors which are highly effective in different aggressive environments. This study is based on the corrosion of rebars in simulated concrete pore solution in the presence of 3.5% NaCl with oxalhydrazide as the potential inhibiting material. The corrosion behaviour of rebar is obtained by electrochemical studies using EIS and potentiodynamic polarization and theoretically analysed employing molecular mechanics and molecular dynamics simulations. The experimental results revealed that the inhibitor is effective in reducing the corrosion and the values of binding energy of the inhibitors on rebar surface also go well with the experimental results. Oxalhydrazide is found effective in minimizing the attack of chloride ion on rebar in pore solution.
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Jeon, Woo-Seck, and Il-Cho Park. "Effect of Marine Coolant Additives on Cavitation Erosion–Corrosion of Diesel Engine Cylinder Liner." Applied Sciences 15, no. 11 (2025): 6353. https://doi.org/10.3390/app15116353.
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In this study, cavitation erosion tests were conducted to investigate the effects of the presence of coolant additives and chlorides on the corrosion and cavitation erosion of cylinder liners in marine diesel engines. Electrochemical experiments were conducted to evaluate the corrosion characteristics of ductile cast iron (DCI), and the corrosion potential and corrosion current density were measured. In addition, weight loss, surface roughness, and maximum surface damage depth were quantified as a function of cavitation exposure time. Furthermore, to investigate the erosion and erosion–corrosion characteristics induced by cavitation attack, the damaged surface morphology was closely examined using a scanning electron microscope (SEM) after the cavitation erosion tests. The results revealed that the coolant additive effectively protected the DCI from corrosion caused by aggressive chlorides. In particular, when an appropriate amount of additive was added to a coolant containing 100 ppm of chloride, the corrosion current density of DCI was reduced by approximately 31.7 times, significantly improving corrosion resistance. Therefore, different surface damage mechanisms corresponding to cavitation erosion and cavitation erosion–corrosion were identified depending on the presence or absence of the coolant additive during the cavitation erosion tests.
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Abu-warda, Najib, Sonia García-Rodríguez, Belén Torres, María Victoria Utrilla, and Joaquín Rams. "Effect of Molten Salts Composition on the Corrosion Behavior of Additively Manufactured 316L Stainless Steel for Concentrating Solar Power." Metals 14, no. 6 (2024): 639. http://dx.doi.org/10.3390/met14060639.
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The effects of different molten salts on the corrosion resistance of laser powder bed fusion (L-PBF) 316L stainless steel was evaluated at 650 and 700 °C. The samples were characterized via XRD and SEM/EDX after high-temperature corrosion tests to evaluate the corrosion damage to the L-PBF 316L stainless steel caused by the molten salts. The presence of the salts accelerated the corrosion process, the chloride-based salts being the most aggressive ones, followed by the carbonate-based and the nitrate/nitrite-based salts, respectively. The L-PBF 316L did not react strongly with the nitrate/nitrite-based salts, but some corrosion products not found in the samples tested in the absence of salts, such as NaFeO2, were formed. LiFeO2 and LiCrO2 were identified as the main corrosion products in the samples exposed to the carbonate-based molten salts, due to the high activity of Li ions. Their growth produced the depletion of Fe and Cr elements and the formation of vacancies that acted as diffusion paths on the surface of the steel. In the samples exposed to chloride-based molten salts, the attacked area was much deeper, and the corrosion process followed an active oxidation mechanism in which a chlorine cycle is assumed to have been involved.
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Efeeloo, Ndam, Bright Akoba, and Charles Kennedy. "Mitigation of Steel Corrosion Threshold Utilizing Plant-Based Green Corrosion Inhibitors through Electrochemical Techniques." Saudi Journal of Engineering and Technology 9, no. 06 (2024): 240–56. http://dx.doi.org/10.36348/sjet.2024.v09i06.002.
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Corrosion of steel reinforcement is a major cause of deterioration in reinforced concrete structures. The corrosion process is influenced by the concrete-steel interface, with the alkaline concrete pore solution initially providing passivation. However, ingress of aggressive substances like chlorides can disrupt the passive layer, initiating active pitting corrosion above a threshold level often taken as 0.4% chloride by cement weight. Once the chloride threshold is exceeded, corrosion propagation depends on oxygen and moisture availability. The resulting rust formation causes expansive cracking and spalling of the concrete cover. Corrosion damage can be mitigated through use of inhibitors like calcium nitrite though high dosages impair concrete strength. Recently, plant-based organic compounds have shown promise as green corrosion inhibitors. The corrosion behavior of steel in concrete can be evaluated through impressed accelerated corrosion testing along with electrochemical techniques like half-cell potential mapping and resistivity measurements. These allow assessment of the probability of corrosion and corrosion rate. Techniques like linear polarization resistance and electrochemical impedance spectroscopy can also quantify instantaneous corrosion rate. Proper structural condition assessment and repair using both conventional and green inhibitors is crucial to control steel corrosion, maintain service life and ensure safety. Further research is needed on green corrosion mitigation methods and advanced non-destructive testing techniques.