Lab Report Sample

Lab Report Paper To conduct a vive analysis, samples are oven dried tort at least 24 hours. The soil is placed and shaken through a stack of sieves with openings of decreasing size from top to bottom. The mass of particles retained in each sieve is determined. Results showed that the particle-?size distribution curve of coarse aggregate is characterized by a steep curve. This means the coarse aggregate is poorly or uniformly graded with small variation in size Particle-size distribution curve of fine aggregate is characterized by an S-curve. It is well graded and has a gradation of particle size that spans evenly the size from coarsest to finest. Conclusions drawn from the interpretation of the particle-size distribution curve is supported by computed coefficients Of uniformity and gradation Which is 6. 79 and 1. 03 for (well graded) fine aggregates, and 1. 57 and 1. 05 for (poorly graded) coarse aggregate. Significance of the Experiment Particle size analysis is important because it determines the soil gradation, which is an indicator of other soil properties such as compressibility, shear strength, and hydraulic conductivity. A poorly graded soil will have better drainage because of more void spaces. A well graded soil is able to be compacted more than a poorly graded soil. Standard Reference ASTM CLC 36-06 Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates. Pennsylvania, US: ASTM International, 2006. I. OBJECTIVES After performing this test, the students are expected to: 1. Determine the percentages of various size fraction on the basis of the total mass of the initial dry sample. 2. Determine effective grain size after plotting particle size distribution curve (percent finer versus particle diameter in millimeter). . Calculate coefficient of uniformity and curvature and classify aggregates into well graded or poorly graded aggregates based on given criteria or these two parameters. II. EXPERT MENTAL PROCEDURE A. Materials and Equipment Sieves No. 4, 8, 16, 30, 50, 100, and 200 for fine aggregates Sieves No. I-IM 3/4- IM, 1/2-in. , and 3/8-in, for coarse aggregates Balance accurate to C, I-g for fine and 0. 5 for coarse aggregates Oven Brush B. Methodology 1. Preparation of the Soil Sample. Minimum of 300-g fine and 5-keg coarse aggregates are obtained. We will write a custom essay sample on Lab Report specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Lab Report specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Lab Report specifically for you FOR ONLY $16.38 $13.9/page Hire Writer These samples are both oven dried for at least 24 hours. 2. Preparation of Equipment. All mass of sieves including the pan are determined. Then, sieves are nested in order Of decreasing size Of opening from top to bottom. . Sieving. The sample is placed in top sieve. The sieves are agitated by hand in a vertical and lateral motion. 4. For course aggregates, the sample is split into two or more batches, sieving each batch individually. The mass of the several batches retained on a specific sieve are combined before calculating the percentage of the sample on the sieve. . Sieving is continued for a sufficient period and in such manner that not more than 1 % by mass of the material retained on any individual sieve will pass that sieve during 1 minute of continuous hand sieving. 6. The mass of each size increment is determined on balance. The total mass of the material after sieving should check closely with original mass of sample placed on the sieves. NOTE: If the amounts differ by mor e than 0. 3 based on the original dry sample mass, the results should not be used tort acceptance purposes. C. Data Analysis l. The mass of soil retained in each sieve is computed by getting the difference of mass of sieve with the retained soil, and the product of no of batches made and the mass of sieves. 2, The percent retained is computed by getting the ratio of mass of retained soil on each sieve, and the initial mass of the sample. 3. The recent finer is computed by getting the sum of mass of soil retained on smaller sieves, subtracting it from the total mass of sample, and dividing the sum by the total mass times 100. 4. Percent finer is plotted on y-axis while the particle size diameter in logarithmic scale is plotted on x-axis. A curve connecting the points is drawn. Logarithmic scale is used to represent grain size information that typically spans many orders of magnitude. 5. Important parameters in computing coefficient Of curvature and uniformity such as effective grain size (DID), DID, and 060 are determined from the particle size distribution curve for fine and coarse aggregates. Ill. RESULTS OF EXPERIMENT Particle-Size Distribution Curve and Determination of 060, 030, and DISC Figure 1. Particle-Size Distribution Curve (Fine Aggregates) Figure 2. Particle-Size Distribution Curve (Coarse Aggregates) lb. DISCUSSION Effective Grain Size (DID). It represents a grain diameter for which of the sample will be finer than it. It can be used to estimate the permeability. The effective grain sizes in fine and coarse aggregate in this test are C. 14 mm and 10. 4 mm respectively. These values are obtained from the particle size distribution curve shown in Figures I and 2. Coefficient of Gradation (C). This parameter (also called as coefficient Of curvature) can be expressed as: where; DISC, 030, and DID the particle-size diameters corresponding to 10, 30, and 60 respectively, passing on the cumulative particle-size distribution curve. Fine and coarse aggregates are thought to be well graded fiftieth coefficient of curvature (C) is between 1 and 3. The calculated coefficient of gradation is 1. 03 for fine and 1. 05 for coarse aggregates. Coefficient of gradation is only one criterion in grading aggregates. Gradation also considers uniformity coefficient which will be discussed in next section. Uniformity Coefficient (Cue). This is defined as ratio of the diameter of a particle of a size that is retained in sieve that allows 60% of the material to pass through, to the diameter of a particle of a size that is retained in a sieve that allows of the material to pass through. This can be simply expressed as: An aggregate is thought to be well graded if the coefficient of uniformity (Cue) is greater than 4 for coarse (gravel) and 6 for fine aggregate (sand). Calculated values for this parameter are 6. 59 and 1. 57 for fine and coarse aggregate. Classification. Coarse aggregate is composed mainly Of gravel and crushed stones which pass 3-inches sieve but are retained on No. 4 sieve. Fine aggregates is mostly sand Which passes NO. 4 sieve but are retained on NO. 200 sieve. The experiment showed that the samples used are poorly graded gravel and well- graded sand. Both Of the aggregate pass the criteria for coefficient Of gradation which value should lie between 1 and 3. Fine aggregate is well graded sand with uniformity coefficient greater than 6. Coarse aggregate coefficient of uniformity is very small and did not exceed 4. Coarse aggregate sample is poorly graded ravel. V. LABORATORY SUGGESTIONS Suggestions for Laboratory Improvement Here are some of my personal suggestions that I believe will help in improving the laboratory: Acquire New Lab Materials/Repair Old Materials. Some of the materials in the laboratory really need repair or replacement. Use and borrowing of some materials and equipment are sometimes on a first-come, first served basis because of limited availability. VI. SUMMARY AND CONCLUSION Coarse aggregate is composed mainly Of gravel and crushed stones While fine aggregate is composed of sand. Particle-size distribution curve of coarse aggregate is characterized by a Steep curve. This means the coarse aggregate is poorly graded (uniformly graded) and has small variation in size. Particle-size distribution curve Of fine aggregate is characterized by an S-curve. Fine aggregate is well graded and has a gradation of particle size that spans evenly the size from coarsest to finest. This conclusion is supported by computed coefficients of uniformity and gradation which is 6. 79 and 1. 03 for (well graded) fine aggregates, and 1. 57 and 1. 05 for (poorly graded) coarse aggregate. Manual sieving procedures can be ineffective because the amount of energy seed to sieve the sample is varying. Lab Report Sample Lab Report Paper Osmosis happens when water diffuses across the membrane from the region of lower solute concentration (higher free water concentration) to that of higher solute concentration (lower free water concentration) until the solute concentrations on both sides of the membrane is equal. (Reese, 2011). Active Transport is the type of transport of molecules where energy is supplied to the transporter system to transport in the direction opposite to a concentration gradient. (Hickman, 2008). The objectives of our experiments are to characterize the plasma membrane and to differentiate diffusion, osmosis and active rainspout. II. Methodology A. Structure of the Plasma Membrane i. We mixed 5 ml of water and cooking oil into a test tube by shaking it. Then we observed the mixture as it settles for five minutes. We shook the test tube again and took a sample into a slide before it settled. We observed it under the LOOP of the compound microscope. Ii. We placed cooking oil into a Petri dish, and dropped an egg solution into it. We observed it for a formation of a membrane, then puncturing it. Iii. We placed the evaporated milk in a beaker until it is % full and heat it. We will write a custom essay sample on Lab Report specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Lab Report specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Lab Report specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We then observe the formation of milk skin at the top. Second is to remove the milk skin and heat again. Observe what happens. B. Selective action of the Plasma Membrane i. We prepared three test tubes, L abele accordingly, with Mil of aqueous yeast suspension and three drops of Congo red solution. We added 4 drops of 40% formalin into the first test tube, heated the second one, and let the third stand as it is. We each took a drop of each in a slide and observed it. Ii. We placed 10 ml of alkaline yeast suspension in a 100 ml beaker then added 10 ml of Neutral red Solution. After observing it, we filtered 5 ml of the mixture through a filter paper o separate the yeast from the liquid. C. Permeability i. Diffusion a. We placed a pinch of Potassium Permanganate (Km) and Methyl-blue crystals on top of an agar that was in a Petri Dish. B. We filled up a test tube with a collision solution and slowly rotate it until a thin film covers the entire inner surface of the test tube. We placed the test tube in a rack in an inverted position to let it dry. After ten minutes, we removed the collision gently and slowly with the use of water. We poured in a part of 50% glucose and 2 parts of starch solution. We tied the end of the collision and rinsed its outside. We let it soak in a ml beaker containing ml water and ml 2% iodine. After two minutes, we took samples of the solution and tested it with iodine potassium iodide, for testing the presence of starch, and Benedicts solution, for the presence of Glucose. Ii. Hemolytic and Creation of Red Blood cells. We prepared three slides with 1-3 labels. Then, we paced a drop of 0. 9% Nasal on the first, 10% Nasal to the second and a drop of distilled water on the third. Then we had a volunteer to put a drop of his blood to each of the slides. Then we covered the slides with a cover slip and viewed it under the microscope. Ill. Results and Discussion i. When we mixed the oil and water, it assumed a yellowish-whitish color which gradually separates from each other. And when we viewed the mixture under the microscope, the image that it showed was bubbles, water molecules, which are not really mixed in the oil. Ii. The egg solution Looked like a bubble in the oil. Then when we ruptured its membrane, the egg solution spreads in the oil. And it formed another membrane- like envelope. Iii. After we removed the first skin that formed, another skin formed. The skin is formed due to the chemical reaction hat affects the structure of proteins and fat molecules. When water evaporates from milk during heating, the milks protein and fat molecules become more condensed on the surface. B. Selective action of the Plasma Membrane i. The results of this experiment are in a table below. Test Tube # Content/Procedures Observations Alkaline yeast suspension, Congo Red solution and formalin. The mixture had a dark reddish-violet color. 2 Alkaline yeast suspension and Congo Red solution heated on an alcohol lamp. As we were heating it, the mixture darkened slightly, a few shades darker than the third. Alkaline yeast suspension and Congo Red solution left as it was. This was left as it is and has a bright red solution. Ii. When we mixed the alkaline yeast suspension with the red solution, the Neutral red solution assumed a dark red color. When we filtered the yeast, the cells in the filter paper have a deep red color and the residual solution has a ye llowish-orange color. The color of an acidic solution is Red, while a basic solution is yellow-orange. The cells affected the extracurricular fluid, such that the basic Ph level of the suspension was affected. Since the yeast cells are very acidic, even in basic solutions, it goes through diffusion until the whole solution is in equilibrium. When we filtered the cells, the alkaline solution went bank to its original basic nature. C. Permeability a. When we placed the Km, which originally has a blackish-brown color, it diffuses in the agar acquiring a purple color. And after some more time, it became reddish-orange color. While the Methyl blue crystals diffused at a much slower rate. It has a deep blue color. Just like in an Agar, Small molecules can pass through the cell membrane by diffusing themselves into the membrane. The rate of diffusion is faster with compounds of low molecular weight, while it is slower with compound with a high molecular weight. B. Observations: Time Test for presence of Starch Test for presence of glucose After two minutes Negative. The mixture did not have any color change. Negative. But after heating the Solution, the mixture had a bluish-brown color. After four minutes Negative. But after heating the Solution, the mixture had a brown color. After six minutes Negative. But after heating the Solution, the mixture had a reddish-brown color. Since all results are negative, there were no molecules that passed through the collision. But there was an observed change in color with the Benedicts test. Ii. Hemolytic and Creation of Red Blood cells The first slide gave an image of an equal coloration of yellow and red. Then the second one showed an image with a red cell with some yellow. While the last gave an image of red with a larger area of yellow. Blood cells have a 0. 9% Nasal in their intracellular fluids. The first slide is Isotonic because the extracurricular and intracellular fluids are in osmotic equilibrium.