Exp 5 Lab Report Example | Topics and Well Written Essays - 750 words

Exp 5 - Lab Report Example The tape served as a spacer. One side of taped area was uncoated and an alligator clip could be connected later be connected. The surface of the tape and exposed glass was wiped using a tissue soaked in ethanol and the ethanol allowed to evaporate. A small amount of titanium dioxide paste was added and quickly spread by pushing with a microscope slide across the taped surface before the paste dries. The tape gave a spacing of 40-50 micrometers and thus controlled the thickness of the titanium dioxide layer. The tape was carefully removing without scratching the TiO2 coating. The glass was then heated on a hotplate in a hood for 10-20 minutes until the surface turned brown as the organic solvent and surfactant dried and burned off to produce a white or green sintered titanium dioxide coating. The glass was allowed to cool slowly. The coating was immersed in raspberry juice for ten minutes until a color change was observed. Remaining solution and solid was gently rinsed off with water followed by ethanol. A carbon coating was made on the conducting side of the second piece of tin oxide glass by passing it through the candle. The carbon which is located on the perimeter of three sides of the glass plate wiped off using a dry cotton swab. The two coated sides of both glasses were placed facing each other and held in place using two clips. Triiodide solution was added at the edge of the plate and allowed to spread through the interface. The current and voltage were then measured. When the dye-sensitized cell was placed in the sun the voltage measured was 3.73 and 3.72 volts which give a power of 930watts and 1193 watts respectively. When placed under the projector the measured voltages were 3.48 and 0.14V corresponding to a power of 97.44 watts and 18.2 watts respectively. From the experiment, it is observed that the highest power output was measured when the solar cell was placed outside in the sun. The solar cell efficiency is based

Biology Essay Example | Topics and Well Written Essays - 750 words - 4

Biology - Essay Example The other is the â€Å"good cholesterol† which is contained within the high-density lipoprotein and is considered to have beneficial actions on the human beings. Cholesterol can have good effects on the human body and it is because of this that the researchers have termed it as being beneficial under some set conditions. What this means is that cholesterol has got a physiological role in the human body and thus anything in excess is pathogenic and could lead to the harmful effects that come part and parcel with cholesterol. As per the good aspects, we find out that the metabolism of cholesterol is regulated and controlled by enzymes that are different in nature and shape as well as the receptors present within the human body. Cholesterol makes for an effective transferring process of the proteins which are present within the liver, small intestine, peripheral cells and plasma. Cholesterol helps in digestion of dietary fats as well as the production of many different hormones. There is evidence that with the increase of high-density lipoprotein within the human body, longevity could be expected, which surely is a positive sign related with ch olesterol. Cholesterol always helps in building the cell walls and is thus a good agent within the human body from this perspective. For cholesterol to always remain as a beneficial entity there is a dire need to have its intake in a very conservative fashion so that the related excess does not create coronary heart disease and other risks which are closely associated. Cholesterol is an equally good building block as far as Vitamin D is concerned. It helps the sex hormones and different important chemicals are made up due to the presence of cholesterol. Also cholesterol helps at building the structure as well as the function of the invaginated caveole and the clathrin-coated pits. There is a serious role of cholesterol within the synthesis and intake regimes of a human diet and is synthesized