Papers by Keyword: Buffer Solution

Abstract: Wastewater is a by-product of industrial and commercial facilities. If not treated, it could cause environmental and health problems. The proposed IoT-Based Real-Time pH Monitoring of wastewater can regulate the disposed waste through web browsers. The device has undergone several trials with wastewater from the chemical laboratory at different pH levels. It gave the signal to the solenoid motor to position either close when the pH level is more significant than pH 7.5 and less than pH 6.5 or open when the pH level is pH 6.5 to pH 7.5. The output's accuracy was measured using buffer solutions at different temperatures. It showed that the value of the pH level varied in temperature with significantly small changes. The system monitoring in the web browser captured the data every minute and saved it in a database for data comparison purposes. The device conformed to the Department of Environmental Natural Resources - Environmental Management Bureau (DENR-EMB) in the Philippines' standard permissible pH level (pH 6.0 to pH 9.0). Using an Arduino NANO microcontroller that served as a central processing unit and a Node MCU to connect the system to the internet, the equivalent output of an industrial pH meter was obtained, allowing the user to monitor the system at any time using a web browser.

Abstract: Oxidized bacterial cellulose (BC) was prepared in Na₂CO₃-NaHCO₃ buffer solution using NaClO as a primary oxidant with catalytic amounts of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) and NaBr at pH 10.5. Ethylenediamine was used as activators to pretreat BC in order to increase the accessibility of primary hydroxyl groups. The structures and properties of oxidized BC were characterized by attenuated total reflection infrared spectroscopy (ATR-IR), elemental analysis (EA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that the reformative oxidation successfully introduces carboxyl groups into BC, and the carboxyl content was found to be 1.34mmol per gram cellulose, higher than that of BC without pretreatment (0.81 mmol/g carboxyl introduced) under the same condition. In addition, the oxidized BC maintained the original structure which could expand the application of BC.

Abstract: In this paper, the work was mainly studying influence of pH on Fenton reaction and gingerol scavenging hydroxyl radical. The antioxidant activity of gingerol was characterized by the scavenging hydroxyl ratio and scavenging hydroxyl ratio was analyzed by the spectrophotometry. Hydroxyl radical was produced by Fenton reaction. In the experiment pH and buffer solution have influence on the scavenging hydroxyl radical and Fenton reaction. Gingerol exhibits a strong scavenging radical activity for hydroxyl radical (OH^.). The scavenging hydroxyl radical of different extractions of ginger oleoresin is different.