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The Quantum UniverseIn the natural world, there are three theories to underpin our understanding. Two of these are from Einstein, and the name of theory is Special and General Relativity. The last one is quantum mechanics. Special and General Relativity is a theory related to space, time and gravity. And the others, such as how particles behave, are connected with quantum mechanics.The impressive result in quantum electrodynamics test is, the calculated information by theoretical physicists and the measurement from experimenters were perfectly matched. And the most esoteric to understand in quantum theory is the principle of concurrency. It explains that the particle can be in several places at once, and the particle has all possibilities. For example, a cat in the box is alive, but can be dead simultaneously.All the big objects are made up of tiny particles. Same with this, the world is filled with small particles which follow quantum theory and the complex phenomena that the particle a measure of the amount of matter in something. Fortunately, Newton also provided the way to measure the mass of objects. These are known as Newton’s three laws of kinematics(motion). Firstly, if there is no force applied to the object, the object always keeps its state of initial motion. Secondly, if the object with a mass, m, is subjected to a force of as much as F, the object will exercise with the acceleration, a. For this action, there is an equation, F=ma. Lastly, every action has the reaction of the same magnitude, and opposite direction. In the real world, the Newton’s law works well, however, in quantum phenomena, the Newton’s second law cannot explain the quantum description. According to the quantum theory, the meaning of force lost its power. We should be aware of ‘Newton’s law is not for every big things and quantum for small things’.In fact, the force is a vector quantity. It means the force has both direction and magnitude. With respect to Newton’s third law as I mentioeally the simple particles, as Davisson and others discovered. In addition, it does not behave like the right waves because it is not a complete and perfect wave.Feynman wrote about subatomic particles, ‘They do not behave like waves and particles, they do not behave like clouds or billiard balls, or weights on springs, or like anything that you have ever seen’. We can assume that the elemental building blocks of Nature are particles, as confirmed by all other experiments. And what is important is how the particles move. It is easy to accept through Newton’s laws so that you do not think more deeply. Particles are simply moved in a straight way or curved by external forces. But by the double slit experiment, we found that this was not correct. Thus, we have to build a new theory that the same particles are spreading. And although it sounds weird, we should make sure that one particle exists simultaneously in different locations.In our new theory, particles such as dispersed dots will ne that you toss a coin, the probability of coming out heads and tails are fifty-fifty. But if you know everything about tossing a coin, like gravity that applies to the coin, the angle at which you throw the coin, or the resistance of the air, you can predict more accurately whether the front will come out or the back will come out. This reflects that probabilities are related to our knowledge. But the probability in quantum mechanics has a different meaning at all. We do not only predict the probability that one particle will be there because of the lack of our knowledge.We have used the mathematical method of the clock to understand physics. Then, we will now introduce the concept of clocks for quantum mechanics as well. Let’s assume that the clock is pointing at 12. The length of the clock’s needle is only 1. What we are curious about here is where the clock needle will be located at the next moment. That is, what is the probability that particles will be located elsewhere over timeis 400%. This is a ridiculous value, and to solve this problem, we will shrink the size of the clocks. Under this rule, called the shrink rule, all clocks are reduced by the square root of the total number of clocks.If there are four clocks, each hand should have a length of half a length. So, the probability of finding a particle is (1/2)2=25%, and since there are also four clocks, it is likely that particles will be found in one of the four clocks. We can imagine that there is the infinite number of the clock, but to make mathematical calculations simple, let’s think that there is a countable number of clocks and also particles move only in two dimensions. Check Figure 7.Figure 7. the picture of three clocks and the point X where the particle will be found at laterThe initial clock is number two, and therefore the position of the particle begins anywhere between clock 1 and 3. Think of an X point that is as far away as the large distance which means a large number of hands. The clock/h

자연과학| 2020.05.04| 14페이지| 20,000원| 조회(134)

물리, 양자, 물리학, 양자역학, 양자학, 양자물리학, Quantum, 양자물리, qu..

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The extraction of Cu(Ⅱ) from solutions with coffee wastes and teaIntroductionHeavy metal is a generic term for metals commonly with a specific gravity of 5 or more, and can be deposited by hydrogen sulfide in an acid solution, such as iron, manganese, chromium, copper, mercury and cadmium. The specific gravity is the term of the ratio of the mass of a substance to the mass of a standard substance which has the same volume with the substance. Even small amounts of heavy metals are harmful to the environment and the human body.Among the heavy metals, copper is often encountered and considered a major environmental pollutant because it is highly toxic. When heavy metals are released into the environment, they circulate in the biosphere and can cause damage to living things along the food chain, and sometimes cause pollution-related diseases (Erickson et al 1996). If even a small amount of heavy metal is stored in the body, they can damage the body's health over a long period of time sinceperiments in the past to remove heavy metals from waste water by using bioadsorbant for green chemistry. Considering the low cost of coffee wastes, there was a study to eliminate copper(Ⅱ) from aqueous systems using coffee wastes, which is the same as this experiment (Kyzas et al 2013), and a recent study has been conducted to remove copper(Ⅱ) and lead(Ⅱ) from the river with the organ substance, banana peel (Castro et al 2011). In both of these studies, researchers reported that the two bioadsorbants, coffee grounds and banana peel, sufficiently deserve to be considered attractive.The spectrophotometry was used to analyse how much copper ion was removed. Spectrophotometry involves measuring the spectral transmittance of a substance, the value of absorbance varies depending on the concentration of the material contained in the solution. The higher the concentration of a solute, copper(Ⅱ) ions in this experiment, the higher the absorbance value, and the lower the concentration, the lowerquired. The cuvette was rinsed 2~3 times, and filled with 0 ppm solution. The filled cuvette was placed inside the spectrophotometer, and zero it. When the cuvette was placed into the machine, the side with the arrow had to be toward the left, and the smooth side of cuvette was wiped with a kimwipe to prevent the finger print remaining on the side. The value of absorbance was recorded in the Excel spreadsheet when the value did not fluctuate no longer. If the recording was completed, the cuvette was washed with the next solution, B. And the absorbance of B solution was measured. This procedure was repeated until the absorbance value of F was recorded.Mass of coffee grounds±0.0001 (g)Original Cu2+ Concentration (ppm) ±0.005Final Cu2+ Concentration (ppm) ±0.005% Copper Removed0.251210.003.6463.600.501210.003.1868.241.003910.002.6273.81Removal of copper (Part B)0.25 g, 0.5 g, and 1.0 g masses of coffee grounds were poured into 15 mL centrifuge tubes. Each has three samples at least. Usingcreased. Contrary to the coffee grounds, the extraction value of copper ions shows a pattern of decreasing as the tea particles' mass increased, demonstrating 62.18% at the mass of 0.2519 g, 59.12% with 0.5012 g and 57.21% with 1.0012 g. As a result, the mass of coffee grounds and tea particles can be a factor that can affect the adsorption rate of copper ions in different ways, respectively. In addition, at all mass values, since coffee residues had a greater removal rate than tea particles, coffee grounds are more effective adsorbents.According to the hypothesis of this experiment, the extraction rate of copper with tea particles was expected to show the same tendency with coffee residues. However, the experimental value was not as predicted. First of all, there are limitations in the experiment process. The error in mass is generated when the mass of substances are measured with a scale and poured into the centrifuge tubes. It is not allowed to use a brush to dust any substances lefe water produced 566,000 litres a day is expected (Kim 2015). From the other recent studies, coffee grounds have the ability to adsorb the lead(Ⅱ), one of the other heavy metals (Lavecchia 2016). As a result of this experiment, it had been identified that adsorption rate increases as masses of coffee grounds and tea particles increase, so it is possible to remove more heavy metals from waste water by using a large amount of coffee and tea grounds. Coffee residues and tea particles were left in the solution for 20 minutes in this experiment, but for more efficient time and quantity control, the further research needs to be conducted to determine the amount of coffee grounds that have the highest efficiency and demonstrate the adsorption depending on the time. With the results, purifying waste water will be done more efficiently, which can support the fact that coffee grounds do not cause pollutions and are an economical and effective material for purifying polluted water. And it can be >.

자연과학| 2020.05.04| 10페이지| 6,000원| 조회(88)

환경, 생물, 화학, 화학실험, Extraction, 구리, Experiment, 불..

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The rate law and effects of temperature and concentration on the reaction rate of a clock reaction1. IntroductionVelocity is used as a measure of how fast an object is moving when expressing the movement of the object. For chemical reactions, the reaction rate is also used as a speed measure of how quickly the reaction occurs. The reaction rate is expressed as the changing amount in the products or reactants over a period of reaction time (Serway 1985). In other words, since it is usually represented by the loss of the reactant to the unit or generation of the product to the unit time, the unit has M/s.There are environmental applications using chemical kinetic in everyday life, the first of which is the decomposition of H2O2 included in the livers. H2O2 is toxic to the human body, and the reaction of H2O2 to decompose and become O2 and H2O occurs slowly. However, absorption to the human body can be avoided by adding a catalyst, which speeds up the reaction process. Another example is faster by reducing the activation energy is a positive catalyst.2I- + S2O82- → 2SO42- + I2 ----- (1): slowI2 + 2S2O32- → S4O62- + 2I- ----- (2): fastThe clock reaction used in this experiment needs to be ensured that both equations are tested under the same flask. When the reaction occurs across the two equations, the rate law is expressed by following the slow reaction (Min 2009).rate() = k[I-]a[S2O82-]b (b=1)In this formula, k is reaction constant, which the value depends on the change in temperature. The value of a and b is called the order of reaction to the reactant. The reaction is referred as the ‘a’ order with respect to iodine, the ‘b’ order to S2O82- and (a+b) order overall. The value of a and b can only be determined through the experiment. The I2, a product generated by the progress of (1), participates very quickly in the (2) reaction as soon as it is formed. When S2O32- is used up, I2 doesn’t disappear, rather it remains in the flask, and from that moment, it reacts with After the experiment was over, the mixed solution was thrown into the waste container.ProcedurePart 1 (to determine the order of I- (a) in the rate law)In every three conical flasks, 25 mL of B solution was poured from the measuring cylinder. With a teaspoon, solid Vitex indicator was added in all flasks.And then, 25 mL of A5 solution was transferred into the flask. The time measurement was started as soon as the A5 solution was being poured into the flask. After swirling the flask a little, the flask was left. When the colour turned into dark blue, the time was recorded in the Excel in seconds.Using the other solutions A3 and A1, the time measuring processes were repeated with the same method. The temperature of the solution was measured.In this part, the concentration of I- was an independent variable, and the reaction rate was a dependent variable. Apart from the independent variable, the experience should be processed under the same conditions.Part 2 (changes in reaction rates at decause it was tested at a constant temperature. It was already given that S2O82- is first order in the rate law, therefore the order of I- could be found by comparing each [I-] with the reaction rate. The following calculation was carried out:= 2a = 1.96, = 2a = = 2.15The average value is 2.06, and it indicates that 2a=2.06. The value of ‘a’ is approximately 1. Therefore, since it is discovered that this clock reaction is the first order to iodine and the first order for S2O82-, the overall reaction order is second order.In order to obtain the rate constant (k), the overall rate law must be checked. From the rate law, rate = k[I-][S2O82-], k is equal to the reaction rate divided by ([I-][S2O82-]). The obtained value of k for A5 is 0.013 Lmol-1s-1, for A3 is 0.012 Lmol-1s-1 and the k value for A1 is 0.013 Lmol-1s-1. For average value of k, k = (k1+k2+k3)/3, it has approximately 0.013 Lmol-1s-1.The whole expression for the rate law: rate = k[I-][S2O82-] (k = 0.013 Lmol-1s-1)In the secondreferred in the method part, and the second reason was that since the colour changed rapidly, it was difficult to find an exact starting point for colour change. The colour changed from light to dark blue colours, but for the exact time measurement, it should be measured when the colour changed to light blue. However, it was hard, and the time until dark blue was measured. Thirdly, the value of k is constant depending on the temperature, but the temperature of the solution was not always same during the experiments. Throughout the experiment, the temperature of the solution varied between 23°C and 25°C, and it affected the value of the rate constant. Moreover, since the concentration of the solution was not be completely correspond to the lab manual book and the volume of solution was measured and transferred by the measuring cylinder, this can cause errors.To compensate for these errors, the average response time of human should be taken into account the measured time. In addition, th/>.

자연과학| 2020.05.04| 8페이지| 4,000원| 조회(136)

반응속도, 일반화학, 화학, 시계반응, 화학반응속도, clock reaction, 아이오딘시계반응

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