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Static Systems for Producing Gas Mixtures
Published in O. Nelson Gary, Gas Mixtures, 2018
Measured volumes of liquids are also dispensed with micro or lambda pipets, as shown in Figure 4.2. They have the advantage of no dead volume, but unlike a syringe, which can dispense a wide range of volumes, a pipet yields only one measured solvent volume. Variable-volume precision liquid dispensers are available and are also shown in Figure 4.2. Micrometer syringes and burets have a reported accuracy of 0.5% and can dispense volumes up to 2 mL.35 Ultraprecision micrometer syringes and burets made of glass and Teflon attain an accuracy of 0.02 to 0.04% when delivering volumes up to 2.5 mL. Variable volume (0.030 to 3.000 mL) gas dispensers are not generally available but have been designed and can yield accuracies in the neighborhood of 0.2%.36
Real-time colorimetric detection of dissolved carbon dioxide using pH-sensitive indicator based on anthocyanin and PVA coated green iron oxide nanoparticles at room temperature
Published in Inorganic and Nano-Metal Chemistry, 2022
Derya Aksu Demirezen, Dilek Demirezen Yılmaz
Carbon dioxide and oxygen gases were produced chemically. Calcium carbonate and hydrochloric acid were reacted to produce carbon dioxide gas. Hydrogen peroxide was decomposed to the oxygen gas in the presence of catalyst manganese dioxide. The PVA-gIONPs-ATH solution was reacted with the gases by using the water-displacement method during the reaction time of 35 seconds. The volume of carbon dioxide gas generated from the chemical reaction at the erlenmeyer flask was measured using the water displacement method. The gas was collected at the burette and the volume of gas that has displaced the water at the burette was measured due to the difference in water level before and after the displacement. The moles of the collected gas were calculated according to the gas stoichiometry law at 25 °C (298 K) and 1 atm (101.3 kPa). The equality of 1 mole gas = 24 L gas was used for the conversion. The mass of gas was calculated by multiplying the molar mass of carbon dioxide (44.01 g/mole) and converted to mg. The collected gas was dissolved in the 0.015 - 0.02 L of the indicator solution. The concentration of the gas (ppm) was calculated by the equality of 1 mg/l = 1 ppm.
Investigation of partially pre-mixed charge compression ignition engine characteristics implemented with toroidal combustion chamber and exhaust gas recirculation
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
Swapnil Bhurat, Shyam Pandey, Venkateshwarlu Chintala, Manas Jaiswal, Aditya Kumar
The in-cylinder air motion and combustion chamber dimensions are significant aspects that decide the performance and emission characteristics of the IC engines (Ganesan 2012). Keeping the prime motive of reducing the HC and CO emissions of the PCCI engine, the HCC piston geometry was replaced with TCC. By following the same volume of a piston cavity in both HCC and TCC, the engine was tested at a constant 1500 rpm with varying engine load conditions. HCC (default) and TCC geometries detailed view are depicted in Figure 2b and a, respectively. As discussed earlier, the TCC piston was fabricated by keeping the same volume as the HCC piston. The measured size of the combustion cavity for both the piston was 34 CC. To ensure the same volume for both the pistons, physical measurements by using an Isopropyl alcohol (liquid) were carried out. It can reach easily to crevices of the cavity due to its low surface tension property. A flat glass plate with a small hole was kept on the piston head. Isopropyl was poured into the piston cavity through the burette from the glass hole. Volume was measured from the amount of liquid poured from the burette. For the same cavity volume, the TCC piston showed increased surface area than HCC piston when measured through CAD drawing, which may further improve A-F mixing. Various test results have shown that TCC geometry produces high NOx emissions (Jaichandar and Annamalai 2012) with increasing combustion temperature because of rapid and improved air–fuel mixing. Therefore, the existing engine setup was operated with EGR to control the NOx emissions.
An effective trimetalic crystalline catalyst for sodium borohydride hydrolysis
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2020
In hydrolysis reaction, NaBH4 decomposes in to NaBO2 and hydrogen according to the specific mechanism given by Çakanyıldırım and Gürü (Demirci and Miele 2010). Even NaBH4 has two moles of hydrogen, the reaction results in twice more because of the water decomposition. Four moles of hydrogen are collected in the burette for each mole of NaBH4. Hydrogen volume in the burette was recorded over time. Hydrogen volume and reaction stoichiometry were used to calculate the moles of decomposed NaBH4. Hydrolysis tests were performed in atmospheric conditions and the hydrogen molecules were small enough to assume that the ideal gas equation was appropriate to determine the exact hydrogen mole numbers. Kinetic behavior of the synthesized catalyst was measured at temperatures of 10°C, 20°C, and 30°C with accuracy of 0,1°C. Instead of increasing the temperature, reactor was cooled down to 10°C and the highest operation temperature was set at 30°C. In this way fast-moving hydrogen level could be slowed and traced well. According to the Arrhenius Law, hydrolysis reaction kinetics became faster with increasing temperatures as shown in Figure 3. Linear and positive slope parts of hydrogen release graphs are used to collect data for reaction order calculation.