In a laminar flow, when the water is moving past the hull at low speed, a smooth flow can be observed. In this flow the molecules of water are flowing past the hull one behind the other in a single file (Hamlin, 1989, p. 50). Laminar velocity profile in a pipe (Gillmer & Johnson, 1932, p. 215) When Reynolds increased the flow rate through the tube, the dye streaks were observed to become sinuous, the unstable, and finally the whole flow became mixed with unobservable dye streaks (Figure 5). This type of flow is called turbulent (Gillmer & Johnson, 1932, p. 214). In a turbulent flow when a ship is travelling at high speed in smooth water, it can be observed that the water closest to the hull is being dragged along at nearly the speed of
The concentration of gases that can be dissolved into seawater from the atmosphere is determined by temperature and salinity of the water. As temperature and salinity increase the dissolution of these gases decrease. The important atmospheric gases found in seawater include: nitrogen, oxygen, carbon dioxide-in the form of bicarbonate HCO3-, argon, helium, and neon. Compared to the other atmospheric gases, the amount of carbon dioxide dissolved is large.
This is to enable the hydrometer to float vertically in liquids. In a liquid of lower density, a higher volume of liquid must be displaced for the buoyant force to equal to the weight of the hydrometer so that it will sink lower. The hydrometer floats higher in a liquid
The ballast tanks of a submarine, which are similar in concept to the eyedropper, fill with air when submerged (displacing water in the sub’s ballast tanks) to cause a submarine to surface quickly. If the submarine were to go below the surface, the ballast tanks would be filled with water instead of air. This swap-out of air vs. water appears to change the density of the
First, 50 mL of the sample was placed into a 250 mL Erlenmeyer flask, and onto a stirring plate. Then, the pH of the solution was measured and adjusted to be within the range of 4 and 6, using nitric acid and sodium hydroxide. After the pH was optimal for the experiment, a single mL of indicator- acidifier reagent was added to the sample. Then, 50 mL of mercuric nitrate was place into a burette and titrated with the sample until the color of the solution turned from blue to purple. The volume of titrant used for the reaction to reach endpoint was recorded.
Surfactants of emulsions are amphiphilic which means it contain both hydrophilic and hydrophobic groups. So when emulsion, the surfactant covers the surface of drops with its hydrophobic part in the drop and its hydrophilic part in the water. Typically, there are four types of surfactants: anionic, cationic, amphoteric and non-ionic. The anionic surfactants such as sodium dodecyl sulphate (SDS) release a negative charge in the aqueous solution. They have a relatively high level of hydrophilicity.
0.825 g Na2WO4H2O (2.5 mmol), desired amounts of acidic ligand and 44.5 mL 30% hydrogen peroxide (440 mmol) placed in an 100 mL flask, stirred for 10–15 min to get a clear solution at room temperature. Then 10.5 mL cyclohexanone (100 mmol) added into it without stopping stirring. Continue stirring the reaction mixture at a reflux temperature for 8 h. After completion of the reaction, the reaction mixture cooled in the refrigerator for 12 h. Then white crystalline product obtained after filtration, washed with an ice water and dried in the air. The product weighted and the isolated yield of the adipic acid calculated which is based on the cyclohexanone that was put in the reaction flask. Mechanism: Experiment No.
The sample was placed into appropriate vials as the liquid (L), and the vial was closed by the stopper. For 59.0℃ (acetone-rich side of azeotrope). 25 mL of chloroform and 75 mL acetone were added into the 250 mL round bottom flask. Small amount of boiling stone was added into the flask. The mixture was then distilled.
The anomalous diffraction approach of Van de Hulst was the basis of this approach (Bricaud and Morel 1986; Bernard et al 2001). Various oceanographic studies on influence and variations of scattering by phytoplanktons in different environmental conditions were based on this approach (Stramski et al 1993; Stramski et al, 2001; Stramski et al 2004). Nevertheless, the assumption of homogeneous sphere is often significantly deviating from actual situation as algal cells have diverse, complex inner structure and shapes. Studies have also indicated departure from the homogeneous sphere simulated models of scattering spectra (Volten et al 1998; Wikoswki et al 1998). Zhou et al (2012) had determined variations of scattering spectra of 14 phytoplankton species in laboratory and found that the highly featured scattering and backscattering spectra of phytoplankton could not be modeled satisfactorily based on Mie theory for homogeneous spheres.