Chilean Copper Mine Collapse Essay Example for Free

Chilean Copper Mine Collapse Essay August 5 at the San Esteban mine, near the city of Copiapo, Chile 34 miners have been missing and presumed trapped after a collapse of the main shaft. At this time it is uncertain of the extent of injuries after the collapse. The Minera San Estaban Primera company; owners of the San Esteban mine have stated mining accidents on a major scale are uncommon in Chile and hopes are high that all the 34 workers made it to the refuge area where supplies are located. Rescuers are underway in hopes of locating all 34 workers alive. The primary method for rescue is drilling holes in an attempt to locate the workers. There are concerns about the amount of oxygen at this depth approximately 100 meters below the surface. With a drilled hole into the shaft where miners are believed to be; needed supplies may be delivered until a full rescue can be attempted. I believe a report more in line with what I wrote about would have been a far more positive way of delivering a hard message to concerned family members, coworkers at the mine, and all humans with concern for these miners. In our text a quote was found from Ralph Nichols. The most basic of all human needs is the need to understand and be understood. The best way to understand people is to listen to them. † If the owners of the mining company had listened to the concerns of the family members a more positive method of communicating the situation and tactics that may be utilized to save these workers. If the San Jose mine owners had attempted to use a central idea and main points while informing the media of their intentions many of the angry family members who received little or no information would not have been as quick to call for safety records. The use of visual support to quickly let the audience know that the company and rescue team was at least working on plan would have been very helpful in easing the minds of the audience. Early in the incident the company gave almost no information to the media or family. A crude outline of the events would have been an improvement in the communication process over the lack of communication displayed early on. A plan of action displayed for the world to see has great value here. Had the company used the fact form of persuasion to deliver a message to concerned audience members many of the family members may have been put at ease somewhat. Had the company stated that Chile had very few major mining incidents in its history this could have went very far to improve the relationship with the media and concerned onlookers. Explaining that supplies would be provided for the duration of this event and these workers would not be abandoned even if it was implied would have been very valuable. The use of value in this communication process letting everyone know that the miners were indeed valued by this company and all that could be done would be done surely would have been a positive and assisted all parties involved. Obviously to discuss policy and or procedures for mine collapse would have persuaded the audience of the company’s determination to do the right thing. This also eases the audiences mind that the company has plans in place prior to an incident. The company did not do any of these things early in the emergency. If the company could have simply stated their intentions to fix this problem and improve operations in the future many of their mistakes could have been forgiven. It may not have been possible early on to discuss the intentions to keep the mine open, if it could have this would have reinforced to everyone that the company would be here throughout the incident and beyond. As many of us know the incident took 70 days to complete and the miners were delivered supplies through a small tube for the duration. Although this story has a heroic and happy outcome; the first few days of the incident was hell for onlookers. Watching video from the incident probably would indicate a need for better nonverbal communications by the mine owners. Neither nonverbal communication, semantics, nor syntax would have changed the family’s grief in the beginning nearly as much as the lack of communication did affect them negatively.

Neutralisation of False Positives using Presumptive Tests

Neutralisation of False Positives using Presumptive Tests   Jasnique Tiwana   The Neutralisation of False Positives using Presumptive Tests for Blood   Abstract Introduction This project emphasis upon neutralising presumptive tests for blood, this differs from other studies as they just test for false positives, instead of attempting to neutralise these known false positives. This project was conducted as there are no current obvious projects on the neutralisation of false positives. This is a crucial topic because it will save time at crime scenes when looking at a suspected blood stain, many false positives are known to interfere with the presumptive tests kits. However, if these can be eliminated at the scene, then it will save lots of time conducting confirmatory tests for a stain that is not blood. It will be interesting to discover whether one neutralizer can neutralise all or the majority of the unknown false positives. The aims of this project are to find out which substance/ products produce false positives, and whether or not these false positives can be neutralised. In addition, how many of these false positives work for both Kastle-Meyers and Leucomalachite green. Also whether the type of surface these false positives are found upon affects the ability for them to be detected. There are numerous amounts of different bodily fluids that can be found at a crime scene. Blood is one of the most common and important bodily fluid found at a crime scene as it can give an insight to a DNA profile and much more. The blood can either be from the offender this can help corroborate stories and give a deeper insight into what actually happened (The Forensics Library, n.d). In the criminal justice system blood is defined as a vital complex biological fluid containing red blood cells, which is present in vertebrate and may be shed during an accidental, intentional and/or criminal acts. (Wonder,2001). Blood consist of erythrocytes, leucocytes and platelets, hence presumptive assays test for the presence of haemoglobin located in the erythrocytes (Jackson and Jackson, 2007). However, at a scene it may not always be obvious as to whether or not the stain is actually blood, thus, presumptive tests are required to determine whether the stain could be blood or not. There are various different presumptive tests designed to identify whether the stain is blood, although, these are not a confirmatory test for blood. Blood found at a crime scene is essential as it can provide a DNA profile from both the victim and the suspect. (Gupta, et, al. 2016). This can then be collected for further analysis in the laboratory, to obtain DNA profiles etc. (Tobe, et, al. 2007). Over centuries various different attempted clean-up methods have been used for blood, including bleach, therefore, it is important to use a presumptive test which can detect microscopic blood stains. Presumptive tests Presumptive tests with the exception of luminol are not applied directly to a stain, instead, the suspected stain is lifted using a sterile swab or filter paper, the presumptive test is then carried out on the filter paper or the swab. This is to ensure that the suspected stain is not damaged. In certain cases, such as where the surfaces have been washed down, it becomes more appropriate to use luminol due to its high level of detection (Jackson and Jackson, 2007). Presumptive tests are used by forensic scientists worldwide to aid in the identification of unknown substances such as blood. However, a presumptive test does not provide definitive identification instead it provides useful information which helps to decide what further action if any is needed. There are numerous presumptive tests for blood, historically with the most common being benzidine which was first introduced in 1904 (after Kastle-Meyers) which was introduced in 1901). Moreover, this is no longer widely used in forensics as it was discovered to have carcinogenic effects. Tetramethylbenzidine has also been recognised as a carcinogen and caution should be applied when using either test (James,1998). Presumptive tests are not specific to Human blood as they will also give a positive result for animal blood. Commonly, a colour change is observed to determine whether it is positive for that substance, due to these presumptive tests are subject to false positives and false negatives. In screening tests for blood, the heam group is observed as this acts as a catalyst which is involved in the chemical reactions. False positive results can be obtained from chemicals containing strong oxidants such as bleaches and household cleaners. Plant peroxidases such as horseradish can also affect presumptive tests such as horseradish as they contain peroxidases they catalyse oxidation reactions thus causing a false positive. They are known to be sensitive to heat so heating up a plant peroxidase can inactivate it. A false positive is identified as a colour change before the addition of hydrogen peroxide (Li,2008). Li (2008) states that although uncommon false negatives can also occur, this happens when a strong reductant is present, this hinders the oxidation reaction. Luminol Luminol is referred to a chemiluminescent reaction which is oxidised by haemoglobin. It was a very early method used in 1937 to detect microscopic amounts of blood at a crime scene as it has a very small detection limit (in nanograms). Although, the test is sensitive it is also prone to false positives as with the other presumptive tests of blood. Sodium Hypochlorite is in bleach based substances commonly used for a clean-up, this would be detected by the luminol test (Quickenden and Cooper 2001). A limitation to luminol is that it must be used in total darkness to be able to see the reaction. It is different from the other presumptive tests as it involves illumination with a bright light (blue) (Webb, et al, 2006). Kastle-Meyers The phenolphthalin Assay is referred to as the Kastle Meyers test, it differs from phenolphthalein which is a class of dye indicator commonly used in titrations. Phenolphthalin is a colourless compound (the reduced form), the oxidized derivative is phenolphthalein which turns pink (Li, 2015). The Kastle-Meyers (KM) test is one of the most popular presumptive test used by forensic scientists, it is possible to detect blood up to 100,000x dilution (Bell, 2012). Figure 1 shows the oxidation of phenolphthalein causing a pink colour change when reacting with a peroxide. The Kastle-Meyers test is a presumptive test used to identify blood stains; it contains phenolphthalein, which reacts with the haemoglobin in blood with the addition of hydrogen peroxide leading to a pink colour change for a positive test. This test, however, is not specific for blood and can be subject to false positives, it is also not specific to human blood and will react with animal blood. Therefore, it is not a confirmatory test of blood. Leucomalachite green (LMG) is also a presumptive test of blood, however; it is not as popular as the Kastle Meyers test (Bell, 2012). A positive result for Leucomalachite green is a green-blue colour change. Leucomalachite green (LMG) Figure 1 to show the chemical structure of Leucomalachite green (Sigma Aldridge, 2017) Leucomalachite Green chemical symbol C23H26N2 (PubChem, 2005), this is also a colour change test it is not as widely used as Kastle Meyers but it is just as useful. Leucomalachite green is oxidised by haem causing a blue-green colour change it is colourless when in its reduced state. The reaction is usually carried out in acetic acid and hydrogen peroxide which acts as an oxidiser (li, 2015). It is used in a very similar way to Kastle-Meyers, as the test is almost identical, this test as with the Kastle- Meyers, therefore, it is also prone to a false positive, hence further analytical tests are required to confirm if its blood. Due to the false positives, it cannot be called a confirmatory test for blood. These tests are also not specific as they do not react to just human blood but other animal blood. Neutralising agents Various different neutralisers are available for bleach. Bleach is known to be a common false positive detected with Presumptive tests. The active ingredient in Bleach is Sodium Hypochlorite, therefore, research into is neutralisation was looked into. The most common one used is Sodium Thiosulphate another is Ascorbic acid which is used more commonly in water storage tanks to climate all remaining bleach making the water safe to drink (Tanguay,2013). Due to the neutralisation of peroxide both these neutralisers will be used to see if they neutralise all the false positives. Method Preparation of the reagents: The Kastle-Meyers test: The reagent is made by weighing out 12g of phenolphthalein, 120g of potassium hydroxide and 30grams of Zinc dust and 600ml of distilled water should then be added. This is then put onto a hot plate and stirred for 3 hours. (Langford et,al). The Kastle-Meyers was used as follows, the stain was moistened with ethanol (optional depending on how the stain was lifted) and this is rubbed over the stain, then two drops of the Kastle-Meyers is then added onto the stain, at this stage a colour change is indicative of a false positive, if there is no false positive at this point then continue to the next stage, and add two drops of 3% hydrogen peroxide, if there is an immediate pink colour change this indicates blood could be present as it is a positive result for blood. If there is no colour change then it can be almost certainly said that no blood is present, this is due to its high level of sensitivity. Leucomalachite green solution was made up using 0.11grams of Leucomalachite green powder, 66mL of glacial acetic acid and 33mL of distilled water, this was mixed together to form the colourless Leucomalachite green (cox, 1991). The same method mentioned above is used for Leucomalachite green with a blue-green colour change being a positive result for blood and a blue-green before the addition of hydrogen peroxide being a false positive. The initial Leucomalachite green solution is clear. Defibrinated horse blood was used due to its similarity to human blood, also because presumptive tests cannot differentiate between blood types. The swabs used were all in sterile packaging and all the pipettes had been autoclaved prior to use to ensure that all equipment used was sterile as not to allow any cross contamination. Blood was placed straight onto a sterile swab; this was subjected to the presumptive tests to ensure no other contaminants caused a colour change this acted as a positive control. Negative controls were created using a sterile swab and adding each of the reagents to make sure nothing else was interfering with the test. A positive control was also taken by swabbing blood from denim to see if it would still react or if there was an interfering factor. To determine the levels of sensitivity for both KM and LMG blood was diluted and put into test tubes. Blood was pipetted into test tubes using Finn pipettes in order to determine accuracy. Different concentrations of blood were made up using distilled water and blood. The solutions made up were 1:10, 1:100, 1:1000, 1: 10,000, 1: 100,000 were prepared. This was done by pipetting 1mL of blood into 9mL of water, from this solution 1mL was added into 9mL of water and so on. This method was used to determine the level of sensitivity of the presumptive tests used a sterile swab was dipped into each of these solutions and the Kastle -Meyers test was performed. The time taken for these to turn and the shade of pink in which they turned were recorded. Each swab was taken 3 times in order to determine accuracy, but also each test tube was made up 3 times, this gave a total of 15 test tubes, to make sure no extra or no less blood was added each time, and to check the reliability of the method a s the blood had begun slightly clotting. This was done over a series of days to see if the results differed in anyway. A series of household items and known false positives obtained from previous literature reviews were determined and these were placed onto the denim material, by rubbing the item onto the material. The items used were, horseradish, bleach, red onion, lemon, tomato, tomato ketchup (Heinz) and potato. These were then allowed to dry on the material before dampening the stain with distilled water. This was repeated three times and also repeated after 3 days when it had more time to dry. With a fresh batch of false positives, horseradish, bleach, ketchup and tomato were re tested to see if they reacted to the new Kastle Meyers and Leucomalachite green solutions. Once the false positives were established such as the use of bleach, then sodium thiosulphate and Ascorbic acid were added to the stains to see if they affected the tests and gave a new negative reaction. Sodium thiosulphate was made up using 0.25g of Sodium Thiosulphate and 5ml of water and mixed to make a 5% solution, the crystals were stirred and the remaining solution was colourless Ascorbic acid was made up using 0.25g of ascorbic acid in 10ml of water, this was then stirred and gives a clear solution. Firstly, a sterile was dipped into bleach and a few drops of the leucomalachite green were applied using a disposable sterile pipette each time, the colour change was then observed. Once this was established another swab was dipped into bleach but this time sodium thiosulphate was first added to the swab, (again using a disposable sterile swab) the sodium thiosulphate was applied all the way around the swab to ensure all areas were covered. In addition, lecucomalachite green was then pipetted onto the swab and observed for a colour change, the same thing was then repeated using ascorbic acid. The swab was held up against a white background to see if It had a slight reaction or not. It was tried with pure bleach and diluted bleach to see if the reactions were the same. The neutralising agents were also used with pure blood to see if it reacted the same with blood and caused a colour change, hydrogen peroxide was added to the pure blood stain. This was to determine whether or not it is a true false positive or not. The next stage was to repeat the following steps using Kastle -Meyers on pure bleach and diluted bleach. In addition, to determine whether or not the false positives worked on all peroxides, both Ascorbic acid and Sodium Thiosulphate were also used on horseradish, in an attempt to neutralise it, this was repeated three times. Results Firstly, a positive and negative control were taken to ensure a positive result was obtained for pure blood and a negative result for water, indicating there was no contamination. A serial dilution was made for the Kastle-Meyers to determine the level of sensitivity. It was measured to a 1 in 100,000 dilution as this is the results obtained from previous literature as to the level of sensitivity. Table 1 shows the intensity of the colour change from the dilution of blood, this was repeated three times. Table 1 a table to show the level of sensitivity of the Kastle-Meyers solution Dilution factor Repeat 1 Repeat 2 Repeat 3 X10 Bright pink Bright Pink Bright Pink X100 Positive Positive Positive X1,000 Positive Positive Positive X10,000 Faint pink Faint pink None X100,000 None None None False positives were first tested on denim to see if they reacted. The blood sample was placed onto the denim material first this was to determine whether the Kastle-Meyers kit was working correctly. The results of the false positives can be seen in table 2, each sample was firstly loaded onto the swab and the denim material, this was too see if there was a difference between the two methods. The highlighted results in table two show the false positives which differed on the denim and the swab. Table 2 shows the first experiment to test for false positives comparing it to the reaction it had on denim. Table 2 false positives using Kastle-Meyers on denim and directly to swab, with* meaning inconclusive result as it is the same colour in which the test kit changes, the samples reacted after 5 mins of the addition of Kastle-Meyers reagent False positive Negative/positive reaction on denim material Added directly to swab Horse Radish root Bleach(Sodium Hypochlorite) + Red onion Potato Tomato sauce + Red Onion Lemon + Tomato * Red radish Leucomalachite green was also tested for its sensitivity of blood This was then tested on pure blood with the addition of hydrogen peroxide. This was to check if the solution made up gives a blue-green colour change. Table 3 shown below shows a serial dilution for Leucomalachite green, the serial dilution was performed in the same way as in the Kastle-Meyers test and the colour change and intensity of the change was recorded Table 3 a table to show the dilution factor of Leucomalachite green after the addition of hydrogen peroxide Dilution factor Repeat 1 Repeat 2 Repeat3 X10 Strong Turquoise Strong Turquoise Strong Turquoise X100 Blue green Light Blue-green Blue-green X1,000 Light Blue-green Faint Blue-green Light Blue-green X10,000 No reaction No reaction No reaction X100,000 No reaction No reaction No reaction Table 4 shows the false positives on the denim material and direct application to the swab, the first repeat the same method applied as that in Leucomalachite green Table 4 false positives using denim material and direct application to the swab, this shows the first attempt using Leucomalachite green False positive Negative/positive reaction on denim material Added directly to swab Horse Radish root + Bleach(Sodium Hypochlorite) + Red onion Potato Tomato sauce Red Onion Lemon Tomato Red radish A fresh set of Known false positives were then used, this was tested with both Kastle Meyers and Leucomalachite green respectively, this is shown in table 5 and 6, each one was tested three times and the reaction and the intensity of the reaction are shown. This time instant colour changes were recorded, using a new Kastle- Meyers test Kit, this was done under a fume hood. This time a diluted bleach sample was used to see if it affected the results of bleach. Table 5 False positives tested using Kastle -Meyers where + means a positive reaction and is a negative reaction, instantaneous results False positive Repeat 1 Repeat 2 Repeat 3 Horseradish + strong pink + pink + strong pink Tomato Tomato Ketchup Bleach + Strong Pink +strong Pink + Strong Pink Diluted bleach + weak pink + pink + weak pink Table 6 false positives tested using Leucomalachite green where + indicates a positive reaction and indicates a negative reaction instantaneous False positive Repeat 1 Repeat 2 Repeat 3 Horseradish + light green + light green + dark green Tomato Tomato Ketchup Bleach + Strong blue/green +strong green + Strong green Diluted bleach + strong green + strong green + strong green Table 7 shows the neutralisation of the false positives identified in table 5 and 6 using ascorbic acid and thiosulphate Table 7 neutralising agents of the false positives for both Kastle-Meyers and Leucomalachite green. where + indicates a positive reaction (colour change) and indicates a negative reaction (no colour change) False positive Kastle- Meyers Leucomalachite green Sodium thiosulphate Ascorbic acid Sodium thiosulphate Ascorbic acid Horse radish + + Bleach + + + Diluted bleach Discussion       The test was repeated three times to see if the results were the same each time. Kastle -Meyers has a level of sensitivity up to 1 in 100,000. This was found to be the level of sensitivity by other authors. Blood was diluted with water; this was not only to test the level of sensitivity but blood is likely to be cleaned up with water of some kind. Leucomalachite green is not as widely used as Kastle-Meyers, as it has a lower level of sensitivity This was diluted in blood to check its level of sensitivity it got a reaction up to 1 in 1,000 rather than 1 in 10,000 as suggested by other literature reports. Denim material had ketchup, tomato, horseradish and blood added to it, however, it did not yield any results as the false positives did not change colour with the addition to lecuomalachite green. Bleach was tested with lecuomalchite green, this gave an instant colour change, bleach was then diluted in water to see if watered down bleach gave the same effect and this also gave a positive reaction. Sodium thiosulphate neutralised the effect of bleach as the reaction was barely visible using the Leucomalachite green, however, the ascorbic acid worked but not as well as the thiosulphate. This is because it was hard to tell whether the entire swab had been neutralised as it appeared a very faint green colour around the sides, compared to other swabs which appeared unaffected by the neutralising agent chosen. It was only tested on the bleach and horse radish because they were the only substances which had given a false positive reaction, None of the substances on denim gave a false positive, this leads to further research into indigo dye as a neutraliser.

Properties of Carbon Dioxide Vapour

Properties of Carbon Dioxide Vapour Greenhouse gases in global warming The greenhouse effect is necessary for Earth to regulate its temperature. Water vapour (H2O), carbon dioxide (CO2) methane (CH4), nitrous dioxide (N2O) and ozone (O3) are some of the gases that contribute to it. These gases are molecules that are made up of more than 2 component atoms. They vibrate upon absorbing thermal infrared radiation and then re-radiate excess energy in all directions. As the Earths surface is now heated by both the emitted radiation and sunlight, temperature increases and thus causing the greenhouse effect. Common Greenhouse Gases Greenhouse Effect Greenhouse Gas Atmospheric Absorption Region on Electromagnetic ( µm) Water vapour (H2O) 95 7600 ppmv 0.8 -10 Carbon dioxide (CO2) 3.618 401 ppmv 2.6, 4, >13 Methane (CH4) 0.360 1780 ppbv 3.5 8 Nitrous oxide (N2O) 0.95 320 ppbv 5, 8 Ozone (O3) 0.072 28 ppbv 0.1-0.3, 9 As shown in the table above, water vapour (H2O) contributes the most to the greenhouse effectWhen temperature increases, air humidity increases as well which is positive water vapour feedback. This allows a higher concentration of CO2 in the atmosphere thus further enhancing the warming effect of other greenhouse gases. Carbon dioxide (CO2) contributes quite a fair amount to the greenhouse effect. Thanks to human activities like deforestation, land use changes and burning of fossil fuel, the atmospheric CO2 concentration has increased by about 120ppm since the Industrial Revolution began, which is more than a third. With an absorption region of 3.5-8 microns on the electromagnetic spectrum, methane (CH4) is way more active than carbon dioxide as a greenhouse gas. Its greenhouse effect contribution is small due to its low atmospheric concentration. Being in a similar absorption spectrum as H2Oalso masks methanes contribution as work might have been done by H2O already. Nitrous oxide(N2O) is typically formed through production of nitric acid, combustion of fossil fuel, agriculture sector and burning of . Even though N2O has a low atmospheric concentration, it still contributes a decent amount to the greenhouse effect. This is because it is up to about 300 times stronger as a greenhouse gas than CO2. As ozone (O3) has various concentration at different parts of the atmosphere and has a short lifespan, it is hard to gauge the contribution of the troposphere ozone layer. Ozone generally does not affect much of the greenhouse effect anyway. Lewis Structures of CO and CO2 Carbon Monoxide a) Rotational Constant, B Taking largest B = 2.04 and smallest B = 1.51 , b) Bond Length, b Reduced mass of carbon monoxide: Since literature value for bond length, b = 113pm lies within the range of , and the uncertainty of calculated bond length value is insignificant compared to the calculated value itself, the calculated value can be said to be quite accurate. c) Vibrational Wavenumber, Distance of first through in P branch from 2050 cm-1= (5.45  ± 0.05) cm Distance of first through in R branch from 2050 cm-1= (5.72  ± 0.05) cm Taking smallest = 2135 and largest = 2143, d) Force Constant, k e) Molar Zero-Point Vibrational Energy, Carbon Dioxide Rotational Constant, Taking smallest = 0.302 cm-1 and largest = 0.46 cm-1, Since literature value for = 0.390 lies within the range of , and the uncertainty of calculated bond length value is insignificant compared to the calculated value itself, the calculated value can be said to be quite accurate. Vibrational Modes CO2 is a linear molecule with 3 atoms. Therefore, it has 3 translational modes, 2 rotational modes, and 3N-5 = 4 vibration modes: 1 symmetric stretch, 1 asymmetric stretch and 2 bending modes. The mode at 667 cm-1 is said to be twofold degenerate because the 2 bending motions are essentially the same, just deforming in different coordinate directions. Exclusion Rule: no modes can be both infrared and Raman active for a molecule with a centre of symmetry. CO2 has a centre of symmetry therefore relevant to the rule. For infrared spectroscopy, the 2 bending and the asymmetric stretching modes can be observed. This is because these modes induce a dipole change in their motions. For Raman spectroscopy, symmetric bending can be seen. This is because when the O atoms move away from the centre C atom in an equal distance, the electron density cloud changes with the change in size of molecule, thus causing a change in polarizability. Bond Length, b Force Constant, k Since literature value for lies within the range of (119.6 ±12.5)pm, and the uncertainty of calculated bond length value is insignificant compared to the calculated value itself, the calculated value can be said to be quite accurate. For symmetric stretch, k CO2 2. Heat Capacity Molar constant-volume heat capacity For CO2: Translational modes, : , Vibrational modes, : , Rotational mode, : Total internal energy, At very high temperatures, the theoretical maximum internal energy = as all modes are activated at that point. Max. constant-volume heat capacity, However, at low temperatures not all rotational and vibrational modes are active. Contributions of different modes at low temperatures: Rotational Modes Rotational temperature, Vibrational Modes Vibrational temperature, Symmetric stretch () : Bending modes () : Asymmetric stretch () : Graph of against T Convert molar constant-volume heat capacity to molar constant-pressure heat capacity with Ideal Gas Law: , (R = ideal gas constant) The graph for experimental and calculated data is the same until around T=1600K where the 2 lines diverge with the experimental data to be higher than calculated data. This shows that the Ideal Gas Law only applies to relatively low temperatures.      Ã‚   Kinetic Theory of Gases and Liquids Mean free path of CO2 Mean free path: average distance travelled by molecules between collisions Rate of collision , : Collision cross-section (area covered by a molecule and within which the presence if the centre of another molecule counts as a collision) Collisions happen at 90o angles on average, mean speed = à ¯Ã†â€™Ã‚   [8]. Viscosity of CO2 vapour Newtons Law of Viscosity: Newtons 2nd Law: Force = rate of change of momentum From plane at 0 from plane : mean flow velocity = à ¯Ã†â€™Ã‚   mean momentum of Roughly1/6th of the molecules move in the +z direction. Number of molecules entering 0 from per unit time = à ¯Ã†â€™Ã‚   rate of momentum = Rate of momentum entering 0 from = . By calculating the difference between the two rates, net rate of the momentum transported across the plane at 0, and by using , the viscosity, can be estimated. [8] (mean velocity), (path length) Viscosity is predicted to be proportional to the square root of temperature and independent of density. Liquefaction in a condenser [9] Modify the Ideal Gas Law to obtain Van der Waals Equation of State. References:[1] https://climate.nasa.gov/causes/ (accessed 14th March 2017] [2] Greenhouse Gas Absorption Spectrum (n.d.) available from:http://www.meteor.iastate.edu/gccourse/forcing/spectrum.html (accessed 14th March 2017) [3] Barrett Bellamy Climate Greenhouse Gas Concentrations (n.d.) available from: http://www.barrettbellamyclimate.com/page22.htm (accessed 15th March 2017) [4] Monte Hieb (2015) Water Vapor Rules the Greenhouse System. Available from: http://www.geocraft.com/WVFossils/greenhouse_data.html [5] Project Learn at http://www.ucar.edu/learn at the University Corporation for Atmospheric Research (UCAR) https://www.ucar.edu/learn/1_3_1.htm (accessed 15/3/2017) [6] Barrett Bellamy Climate Greenhouse Gas Spectra (n.d.) available from: http://www.barrettbellamyclimate.com/page15.htm (accessed 15/3/2017) [7] NIST Standard Reference Database 101 (September 2015) Listing of experimental data for CO2 (Carbon dioxide) Available from: http://cccbdb.nist.gov/exp2.asp?casno=124389 [Accessed 10 Mar 2016] [8] Dr Joao Cabral (n.d.) Properties of Matter Lecture Notes. Department of Chemical Engineering, Imperial College London [9] Steve [2010] The Freezing Point and The Dew Point Part 2 available from: https://stevengoddard.wordpress.com/2010/09/05/the-freezing-point-and-the-dew%C2%A0point-part-2/

The History Of The Internet :: essays research papers

Term Paper: The History of the Internet The Internet began like most things in our society, that is to say that the government started it. The Internet started out as a experimental military network in the 60's. Doug Engelbart prototypes an "Online System" (NLS) which does hypertext browsing editing, email, and so on. The Internet is a worldwide broadcasting resource used for distributing information and a source for interaction between people on their computers. In 1973, the U.S. Defense Advanced Research Projects Agency (DARPA) initiated a research program to investigate techniques and technologies for interlinking packet networks of various kinds. It then expanded to other governmental agencies and then to higher education. This was called the Internetting project and the system of networks, which emerged from the research, was known as the "Internet." Al Gore is described as "an advocate of the information superhighway". He helped bring it to our national attention that he invented the Internet. It is not true that he invented the Internet but it is true that he had a small part in its development. Since the early sixties, when Al Gore was still in high school, the development of networking technology had already started. It is true that the Internet has grown and flourished tremendously during Gore's tenure, but that hardly means he caused it to happen. The Internet has revolutionized the computer and communications world like nothing before. The Internet enables communication and transmission of data between computers at different locations. The Internet is a computer application that connects tens of thousands of interconnected computer networks that include 1.7 million host computers around the world. The basis of connecting all these computers together is by the use of ordinary telephone wires. Users are then directly joined to other computer users at there own will for a small connection fee per month. The connection conveniently includes unlimited access to over a million web sites twenty-four hours a day, seven days a week. There are many reasons why the Internet is important these reasons include: The net adapts to damage and error, data travels at 2/3 the speed of light on copper and fiber, the internet provides the same functionality to everyone, the net is the fastest growing technology ever, the net promotes freedom of speech, the net is digital, and can correct errors. Connecting to the Internet cost the taxpayer little or nothing, since each node was independent, and had to handle its own financing and its own technical requirements.

Free Essays - Animal Farm :: Animal Farm

ANIMAL FARM   About 80 per-cent of all the animals on Animal Farm completely followed the seven commandments.   The other 20 per-cent of the animals would rarely follow all the rules and they were often treated like a piece of dirt.   All the animals on Animal Farm were treated differently according to their social status, where in today’s society everyone should treat everyone equally.   The characters in Animal Farm had many diverse characteristics, some of the animals were powerful, stupid, and sneaky.   First of all, Napoleon is a huge Berkshire boar and he clearly is the most powerful of all the animals.   He was able to take complete leadership of the farm because he secretly trained the dogs to attack Snowball.   George Orwell writes, â€Å" ‘Never mind the milk, comrades!’ cried Napoleon, placing himself in front of the buckets.   ‘That will be attended to, the harvest is more important’ (817).   Napoleon is quite demanding none of the animal’s even question his authority because they know that he has more control than any other animal.   Throughout the novel Orwell has many quotes that describe Napoleon as a leader, â€Å" ‘long live Comrade Napoleon’ † (846).   All the animals on the farm (no matter what Napoleon did to them) would treat him as a powerful leader and whatever he said they would do.   Often Orwell stirs up controversy about the rebellion, â€Å" ‘forward in the name of the rebellion.à ‚   ‘Long live Animal farm!’ ‘Long live Comrade Napoleon!’ ‘Napoleon is always right.’ Those were his very last words, comrades’ † (849).   Squealer’s letting everyone know that no matter what happens to Animal Farm, just remember that Napoleon was an outstanding leader most of the time.   Napoleon was an outstanding leader and contributor to Animal Farm without his power the farm would have collapsed earlier.   Also, basically all the animals on Animal Farm were pretty dumb, they could not read or write.   After Old Major’s death, just three days after presenting his vision to the animals, Snowball and Napoleon quickly become the leaders in planning for the Rebellion because they were the only animals that were smart enough.   Besides from Napoleon and Snowball all the animals did many stupid things on the farm.   The characters in Animal Farm said a lot of stupid things throughout the whole story, â€Å" ‘He is dead, said Boxer sorrowfully.   ‘I had no intention of doing that.   I forgot that I was wearing iron shoes’ † (822).

Existentialism Essays -- Papers Philosophy Essays Papers

Existentialism Existentialism is a philosophical movement that stresses individual existence. Human beings are totally free and responsible for their own acts. Another main idea of existentialism is the limitation of reason and the irreducibility of experience to any system. Man is not a detached observer of the world; rather, he "exists" in a special sense - he is "in the world." Stones, trees, and other objects do not share this existence, and man is open to the world and the objects in it. There is no set limit to how many choices man must make, and no particular set of rules or values one must follow. Rather, there is simply a framework in which action and choice are to be viewed, implying that there are right and wrong ways of choosing, although the individual is still completely free. First, it has been charged with inviting people to remain in a kind of desperate quietism because, since no solutions are possible, existentialists should have to consider action in this world as quite impossible. Existentialists should then end up in a philosophy of contemplation; and since contemplation is a luxury, it must evolve into a bourgeois philosophy. The communists in particular have made these charges. On the other hand, existentialists have been charged with dwelling on human degradation, with pointing up everywhere the sordid, shady, and slimy, and neglecting the gracious and beautiful, the bright side of human nature; for example, with forgetting the smile of the child. Both sides charge them with having ignored human solidarity, with considering man as an isolated being. The communists say that the main reason for this is that existentialists take pure subjectivity, the Cartesian I think, as their starting point; i... ... time, the image is valid for everybody and for our whole age. Thus, our responsibility is much greater than we might have supposed, because it involves all mankind. If I am a workingman and choose to join a Christian trade-union rather than be a communist, and if by being a member I want to show that the best thing for man is resignation, that the kingdom of man is not of this world, I am not only involving my own case-I want to be resigned for everyone. As a result, my action has involved all humanity. To take a more individual matter, if I want to marry, to have children; even if this marriage depends solely on my own circumstances or passion or wish, I am involving all humanity in monogamy and not merely myself. Therefore, I am responsible for myself and for everyone else. I am creating a certain image of man of my own choosing. In choosing myself, I choose man.

Essay --

Love, one of the biggest aspects of human nature, affects everyone in different ways. In the novel by Stephen Chbosky, â€Å"the Perks of Being a Wallflower,† the main character Charlie, negatively affected by his loving relationship with his aunt Helen, develops many social issues. The novel, a coming of age story about overcoming many obstacles as a teenager, follows the main character, Charlie, and the challenges he faces. Throughout the story, Charlie struggles with the loss of his beloved aunt. When he begins High school, he has a harder time than the typical teenager for many reasons. His close relationship with his beloved aunt is the source of his companionship issues, depression, and insecurities. As a result of Charlie’s relationship with his aunt Helen, he develops companionship issues after her death. Having had such a close relationship with her, her passing greatly affects his relationships with other people. A shy, timid, and somewhat anti-social Charlie fears getting close to somebody again after his closest friend has passed. His inability to make friends shows when he t...