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Testing Methods for Chlorides Transport in Cement-Based Materials
Published in Shi Caijun, Yuan Qiang, He Fuqiang, Hu Xiang, Transport and Interactions of Chlorides in Cement-Based Materials, 2019
Shi Caijun, Yuan Qiang, He Fuqiang, Hu Xiang
The method used to determine the water-soluble chloride content is described as follows: Dry the powder (passed through 0.85 mm sieve) at 105°C to constant mass and cool it down to room temperature.Weigh approximately 10 g sample to the nearest 0.01 g and place it into a 250-mL beaker.Add 50 mL of reagent water into the beaker, bring to a boil and boil for 5 min. Allow to stand 24 h.Filter by gravity or suction through a fine-texture. Transfer the filtrate to a 250-mL beaker. Add 3 mL of (1:1) nitric acid to the filtrate.Cover the beaker with a watch glass and allow to stand for 1 to 2 min. Heat the covered beaker rapidly to boiling.1ml solution is pipetted for the determination of the concentration of chloride.
General Atomic Absorption Procedure for Trace Metals in Airborne Material Collected on Filters
Published in James P. Lodge, Methods of Air Sampling and Analysis, 2017
Samples suitable for total dissolution including the clean filter covers and blanks (minimum of 1 filter and cover blank for every 10 filter samples) are transferred to clean 125-mL Phillips or Griffin beakers and sufficient concentrated HNO3 is added to cover the sample. Each beaker is covered with a watch glass and heated on a hot plate (140°C) in a fume hood until the sample dissolves and a slightly yellow solution is produced. Approximately 30 min of heating will be sufficient for most air samples. However, subsequent additions of HNO3 may be needed to completely ash and destroy high concentrations of organic material, and under these conditions longer ashing times will be needed. Once the ashing is complete as indicated by a clear solution in the beaker, the watch glass is removed; and the samples are allowed to evaporate to near dryness.
Methods for the Determination of Inorganics and Nonmetals
Published in V. Dean Adams, Water and Wastewater Examination Manual, 2017
Standard Sulfuric Acid or Hydrochloric Acid, 0.1 N: Dilute 3.0 mL cone H2SO4 or 8.3 mL cone HCl to 1 L with DDW. Standardize against 40.00 mL 0.05 N Na2CO3 solution with about 60 mL DDW by titrating potentiometrically to a pH of about 5. Lift out electrodes, rinse into the beaker, and boil gently for 3 to 5 min under a watch glass cover. Cool to room temperature, rinse cover glass into beaker, and finish titrating to pH 4.5. Calculate normality: Normality,N=M×S26.50×C
Novel Genetic Algorithm (GA) based hybrid machine learning-pedotransfer Function (ML-PTF) for prediction of spatial pattern of saturated hydraulic conductivity
Published in Engineering Applications of Computational Fluid Mechanics, 2022
Vijay Kumar Singh, Kanhu Charan Panda, Atish Sagar, Nadhir Al-Ansari, Huan-Feng Duan, Pradosh Kumar Paramaguru, Dinesh Kumar Vishwakarma, Ashish Kumar, Devendra Kumar, P. S. Kashyap, R. M. Singh, Ahmed Elbeltagi
Textural analysis of the soil was performed using the Bouyoucos hydrometer method (Bouyoucos,1962). Fifty gram of soil sample was taken in a beaker, and 50 mL of 6% H2O2 was added to it. The beaker was covered by watch glass and heated on the heating plate until the organic matter was not oxidized. The content was transferred into a dispersing cup with about 400 mL of distilled water. Then, 100 mL of 5% Calgon solution was added to it, and the suspension was stirred with the help of an electric stirrer for 10 min. The suspension was transferred into a measuring cylinder, and the volume was made up to 1L. It was then shaken vigorously for 5 min with the help of a plunger. The hydrometer was placed into suspension, and readings were recorded exactly after 4 s and after 2 h. The sand, silt, and clay content were calculated, and the textural class was determined with the help of the Textural Triangle. The corrected hydrometer reading = R+(T – 67) × 0.2.
Health risk assessment of heavy metals in irrigated fruits and vegetables cultivated in selected farms around Kaduna metropolis, Nigeria
Published in Egyptian Journal of Basic and Applied Sciences, 2021
Bahiyya Kabir Lere, Ibrahim Basira, Saidu Abdulkadir, Salisu Muhammad Tahir, Hadiza Abdullahi Ari, Adamu Yunusa Ugya
The wastewater samples were digested as follows. The sample, 100 cm3, was transferred into a beaker and 5 ml concentrated HNO3 was added. The beaker with the content was placed on a hot plate and evaporated down to about 20 ml. The beaker was cool and another 5 ml concentrated HNO3 was also added. The beaker was covered with watch glass and returned to the hot plate. The heating was continued, and then small portion of HNO3 was added until the solution appeared light colored and clear. The beaker wall and watch glass were washed with distilled water, and the samples were filtered to remove any insoluble materials that could clog the atomizer. The volume was adjusted to 100 cm3 with distilled water [20]. The concentrations of Cu, Zn, Fe, Cd and Pb in the filtrate of water were estimated using the MP-AES as described in the manufacturer’s instruction manual.
Effect of fly ash on compressive strength and chloride binding of seawater-mixed mortars
Published in Journal of Sustainable Cement-Based Materials, 2019
Faiz Uddin Ahmed Shaikh, Jason Dobson
Once the mortar cubes had undergone compressive strength testing partial remnants of the mortar were collected and crushed into a fine powder with the use of a pestle. The mortar cube remnants were crushed sufficiently into powder to pass through a 300-micron sieve. This process was a requirement for chloride testing as the powder must be fine enough to easily dissolve in solution. The Texas department of Transportation procedure was followed to determine the free chloride in powder samples in this study [17]. A 30g portion of powder was placed into a 400ml beaker followed by the addition of 300ml of deionized water, stirred and then covered with a watch glass. The free chloride contents were only determined in mortar mixed using seawater. These mixes were placed onto a preheated 75 °C hot plate for 2h and stirred periodically at 10 min-intervals. After 2h, the mixes were filtered into a separate beaker with all residues carefully washed off the stirring rod and watch glasses with deionized water. From the resulting solutions 2ml was extracted and placed in small testing capsules used in conjunction with the Aquakem v 07 chloride testing facility in the laboratory. Two samples from each mortar mix were captured along with initial chloride levels for seawater and potable water. Testing for pH was done using a potable pH tester.