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Vehicles and Factories produce Harmful gasses. How can we minimize this problem
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Vehicles and Factories produce Harmful gasses. How can we minimize this problem?
Introduction of the problem
Vehicle and factories have been the main contributors of harmful gases that have led to accelerated global warming. The problem of toxic gases has been one of the top topics of discussion in many governments as they explore ways and means of minimizing the problem. In addition, the harmful gases from vehicles and factories not only cause environmental pollution but also cost the government a lot of revenues in holding campaigns and training on how to use environmentally friendly machines. A solution to minimize such effects would be most recommended because the government cannot order shutting down of factories nor can it get rid of all vehicles responsible.
Defining the problem
Every living thing requires a clean and healthy atmosphere in order to survive. The harmful gases produced by factories and vehicles have turned earth into the worst living place in the whole universe. The main problem arising from the issue of production of harmful gases is the lack of appropriate methods of minimizing the gases. The efforts of many nations to go into using green energy have been rendered weightless. This is because people are either unwilling to change or, lack of adequate resources to implement the plan.
Proposed solution
The production of harmful gases from the vehicle and factories could be minimized by the following proposed solutions. All countries should encourage the use of green energy, or the renewable energy sources such as solar energy, wind energy, and hydropower energy. Factories and vehicles use engines run by fuels such as petroleum and fossil fuels. Such fuels consume a lot of carbon leading to production of harmful gases in the form of carbon monoxide. Consequently, these harmful gases lead to air pollution and more importantly destroy the ozone layer that contributes to global warming. The introduction of renewable sources of energy would serve as the best solution for this problem. According to State Energy Resource Centre, renewable energy sources reduce the pollutions from factories and vehicles engine products. In addition, the renewable sources reduce the energy consumption from fossil fuels and petroleum by 25-75%.
The implementation of this solution would be the most effective method of minimizing production of harmful gases from factories and vehicles. The implementation process would require the government putting up policies that prevent upcoming factories from using fossil fuels or petroleum in running engines. Moreover, the government should focus of production of battery powered vehicles and sell them at reasonable prices.
Other solutions
Even with efforts of environmental management authority to provide solutions towards minimizing of harmful gasses production, some solutions have never succeeded. The United States Engineers introduced smokeless engines as a method of minimizing production of harmful gases. The following method has little effect on minimizing gas production because no engine can run without exhausting smoke. Although the effect is limited, it ends up polluting the environment in future (Associated Press 2013). Secondly, the solution to arrest and prosecute owners of smoke producing engines and factories is another solution that failed. The high rate of corruption could not allow even a single person to be prosecuted and the problem kept on increasing.
Conclusion
In conclusion, the impact of global warming had affected many people and resulted into loss of many lives globally. People ought to turn into using renewable sources of energy in order to minimize effects of harmful gases. Moreover, the government officials should be on the leading position calling for citizens to take care of the environment in order to increase the life span. The following proposed solution forms the best practice that any country can follow to minimize the production of harmful gases from factories and vehicles.
Work cited
Associated Press. Navistar reveals prototype for smokeless engine. 2013. Retrieved from:
http://www.apnewsarchive.com/1989/Navistar-Reveals-Prototype-for-Smokeless-Engine/id-1e0a41d52f937400739a3905d79f1d1b
State Environmental Resource Centre. Renewable Energy Incentives. 2013. Retrieved from:
http://serconline.org/RenewableEnergyIncentives/
Diet and Behavior research paper
Diet and Behavior research paper
Now in days us humans eat many kinds of foods, some that are good for us and others that aren’t. Many of the foods that we eat can have an impact in our behavior and learning mood in a number of ways, there is increasing interests between what children eat and the way they behave, like for example if you decided to give a candy or something that contains a lot of sugar in it to a kid that’s about five years old, he or she will be all hyped up after eating the candy and if the kid is in school it would be difficult for the kid to concentrate due to the fact that he’s not calm enough to learn. But not everything we eat gives us a negative impact in our lives.
On January 30, 2008 the Associate Parliamentary Food and Health Forum made a research which looks at the scientific evidence on whether mental health and performance can be affected by what we eat, and explored how this could be happening. This research supported what the Farm Service Agency once said, that fish consumption should be increased since it is the prime source of omega-3 which helps the pregnant and breast feeding mothers in the brain development of the baby. Food and behavior 9/19/08, HYPERLINK “http://www.fabresearch.org” www.fabresearch.org
In the year 1900 Americans consumed about 4 pounds of sugar a year, now they consume about 129 pounds a year, a 2500% increase in sugar consumption. Food additives and junky diets have high sugar content and starchy carbohydrates that could help explain poor school performance, criminal behavior, alcoholism, and the growing numbers of alzheimer’s patients. Sugar has a big influence on the brain function and physiological function, while sugar is on excess on the brain it produces excess release of insulin, a hormone composed of fifty one amino acid residues which is used medically to treat some forms of diabetes mellitus, when insulin is released you get hypoglycemia if it’s on excess which is low blood sugar, that affects up to 20% of U.S. adults and can cause varying behavior, hyperactivity is often the response in younger children, many children and adults also become violent and aggressive, mental confusion can often be the result for older people as the low blood sugar fails to fuel the brain making it more proem to alzheimer’s. Many people recall that kind of confusion, for example some of them would drive to get something to eat and on their way back home they did not remember where they came from, due to the fact that they had consumed some of the flavor enhancing food additive which can produce hypoglycemia on it’s own those additives can hide when looking at the Nutrition Facts under names like, Hydrolyzed corn, Autolyzed yeast, Broth, and even natural flavors. How food affects behavior 9/19/08, HYPERLINK “http://www.cbn.com” www.cbn.com.
Another danger is alcohol because it acts just like sugar, that is one of the reasons an alcoholic continues to drink alcohol is because alcohol is a tremendous source of energy, according to Russell Blaylock, a medical doctor, when a persons blood sugar falls they drink the alcohol to feel better and then their blood sugar falls again and they drink more alcohol, which is an unending cycle. On a study, they found that 97% of alcoholics are to be hypoglycemic, another study showed that people that have hypoglycemia and are treated with nutrition 70% of them become sober, under other methods 25% or less are under recovery. The diet soda sweetener aspartame contains alcohol, that fact and the way it stimulates the release of insulin help explain why it causes hypoglycemia. How food affects behavior 9/19/08, HYPERLINK “http://www.cbn.com” www.cbn.com
Now kids that eat candy bars such as M&M’s, snickers and others, is equal to one can of soda, the results are very bad such as, their test scores went down after one hour of taking the sugar. Kids made twice as many mistakes on the test and also the students show more inappropriate behavior during free play and current research states that 75% of all prisoners were hyperactive as children. Many drugs that people consume such as the SSRI drugs that are used to regulate and make your brain serotonin go up which helps some people treat their depression, anxiety disorders, and some personality disorders, sometimes it could cause the opposite on some people according to Russell Blaylock, and other medical doctors, it could instead make your brain serotonin go down and this people would commit suicide, or commit murder, that is why a couple of years back we saw all this kids killing people in schools because of the fact that they were taking the SSRI medications.
One of the things people and physicians don’t think about is food allergies that affect your brain, kind of like a brain allergy, when you eat those foods they enter your bloodstream as whole food components which is something that people are not supposed to do, then your immune system recognizes them and you get an immune reaction and that intense immune reaction also goes on in the brain so it releases toxic components which causes a neurological dysfunction that causes symptoms such as disorientation, hallucinations, agitation, panic attacks, criminal behavior and even seizures. Ironically people who are allergic to a certain food and don’t know it, desire more of the same food and every time they eat it they will get sick, and complain that they couldn’t think very clear, so after they were put under treatment and stopped eating the foods they were allergic to they were once again able to think clear without a cloudy mind. The same effect happens with over vaccination, but one major difference is that when you inject the vaccine, the immune reaction goes on for years non stop, that is why we have so many kids with an inflamed brain that will not calm down, and that’s what produces brain dysfunction which was shown in numerous kinds of studies. The major foods that cause food allergies are milk, they looked at many juvenile offenders and found out they drank more milk than average person, others are wheat, corn, coffee, eggs, potatoes, peanuts, and soy which is one of the leading food allergy that most people don’t know about.
One good resource for all this problems would be diet that means you should consume lean meat and lots of fresh fruits and vegetables, which is anti hypoglycemic. Another key is to watch those sugars and starches like sugar itself, products with corn syrup, most fruit juices, white bread, white rice, and white potatoes. By avoiding most processed food you’ll also be more likely to not get any of those hypoglycemic symptoms. There are also some fatty acids that could help people with many personal disorders such as depression, dyslexia, and ADHD, those are oily fish such as tuna, and sardines, also sunflower seeds, and pumpkin seeds. These are the building blocks of a good brain development, similar to the liquid fats which are 65 percent of what our brain is composed of, so what they will do is keep the membrane flexible and allow brain cells to signal efficiently. Those are a couple of the things we humans could do to avoid problems with our health and behavior.
To determine mechanical properties of concrete.
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Subject
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Material Concrete
Abstract
Concrete acts as one of the most essential and cost-effective construction material made from a mixture of sand, cement, aggregates, and water. Cement acts as a binder for holding all the components together. Engineers working in the construction site must understand the purpose of the construction because different structures require different concrete strengths. The strength of cement paste used controls the overall strength of concrete that depends on the water-cement ratio. The following experiment was conducted to investigate different mechanical and physical properties of concrete.
Objective: To determine mechanical properties of concrete.
Materials used: Aggregate (coarse and fine), sand, cement, water, compressive machine, cylindrical and rectangular molds, timer, and computer.
Tests conducted: The main tests done to determine mechanical properties of concrete were slump test, compressive strength test, modulus of rupture, modulus of elasticity, and split tensile stress.
Results: after the lab experiment, it was realized that the material used to make concrete, coarse of fine aggregates, determine the strength of that concrete mixture. Additionally, water-cement ratio determines the strength of concrete. Samples with higher water-cement ratio recorded higher compressive strength, high modulus of rapture, higher split cylinder strength, and higher elastic modulus strength compared to samples from low water-cement ratio. On the other hand, air-entrained concrete had lower strength.
Conclusion: The experiment concluded that the strength of concrete mix depends on water-cement ratio, size of aggregates, and compaction rate.
Problem statement
Concrete mixtures are designed to meet specific physical properties depending on the purpose of the structure. Experts have been conducting many experiments to investigate the effects of different strengths of concrete. The following concrete lab aims at determining the strength of cement concrete. The main factors that influence the strength of concrete that will be tested are the type of mixing design used, mixing procedure followed, and curing period. The test determined the strength of concrete in 7 days strength and 28 days strength in order to determine compressive strength, modulus of rupture, and tensile strength for using different water-cement ratios. Additionally, the lab aimed at testing the differences in strength between normal concrete and air-entrained concrete. Air entrained concrete forms the best discoveries in the field of construction. The concrete contains small and stable air bubbles uniformly distributed over the cement paste. Air entrained concrete is freeze resistant, improves workability and reduces bleeding in areas exposed to extremely low temperatures (Kerkhoff 3). On the other hand, normal concrete occurs in densities of between 1900 and 2600 kilograms per cubic meter, and the majority of the aggregate occurs naturally.
Experimental method
Mix design method
The mixing procedure was conducted using three different batches of concrete; these were air-entrained, normal and super-high strength concrete. Each mix design used different water-cement ratios that define the strength of concrete. The main ratios used were 0.45, 0.5, 0.55, and 0.6. The three mixtures, air-entrained, normal, and super-high concrete were tested for each of the four water-cement ratio mentioned, the three. The class was divided into four groups with each group conducting the experiment using specific water cement ratio. Each concrete sample was supposed to be 10 cm for each mixture. Type I-II cement with a specific gravity of 3.15 was used in all tests. Additionally, the course aggregate had an average diameter of 18mm and with a bulk density of 2.53, and dry rotted unit weight of 1480 kg/m3. The moisture content of aggregate was 0.7% with an absorption rate of 1.9%. Moreover, the fine aggregates recorded a fineness modulus of 2.79, bulk specific gravity of 2.56, moisture content of 0.6% and absorption of 1.1%. According to Prowell, Jingna, and Brown, aggregate accounts for 60 to 70 percent of the total volume of concrete, and 80 percent of the total weight (12).
The amount of water content available in the aggregate determines the water cement ratio to be used. The ratio is calculated from PCA manual. With the known water-cement ratio, the minimum requirements for the cement mixture were identified. The fineness modulus helped in determining the exact volume of coarse aggregate content, also derived from PCA manual. In order to get the total volume of materials used to make the concrete mixture, the bulk specific gravity of each substance was divided by unit weight of water. The air content in the concrete is derived from the product of water content of aggregate and with 27 ft3. Testing for air content is done on concrete to control the damage caused from freeze. Air test helps in establishing the total content of the air entrained in concrete (National Precast Concrete Association 2). On the other hand, the volume of fine aggregate content was calculated by adding up all the constituents and subtracting 27 from the total. Moisture adjustments were done for both course and fine aggregates because they contain a certain level of moisture. Water was added to fine, and coarse aggregate that had low absorption rates and SSD in order to arrive at the required moisture level.
Mixing procedures
The mixing stage is where all constituents were mixed carefully to come up with a concrete mixture. Coarse and fine aggregates were stored outside the lab while the cement was placed inside. All materials were put in different buckets for easier transport and volume determination. The weight of materials in the bucket was taken and recorded until the desired weight was reached. After getting the correct weight of each material, they were poured into the mixer starting with coarse aggregate, fine aggregates, sand, and then cement. The mixer was turned on and allowed to run for 10 minutes in order to mix all the contents. After 10 minutes, it was assumed an uniform mixture of constituents was attained, and the measured amount of water was slowly poured to the mixer in order to allow uniform bonding of materials. Additionally, the mixture was tilted at an angle of 90o, 45o from each side in order allow all material to mix uniformly from the bottom to the top. After the material was mixed for 30 minutes, the mixer was turned off, and the concrete mixture that was stuck to the sides was scrapped off to attain an uniform mixture. The mixer was turned on for the final turn in order to ensure all constituents were well mixed. The teaching assistant checked whether the content had fully mixed and ordered the machine to be turned off completely. The concrete mix was then poured into a wheel barrel and transported inside the lab.
Testing procedures
Slump test
Slump test on concrete is done to determine the consistency of fresh concrete. The test assisted in checking whether the correct amount of water was added to the mix. The test must be done immediately after mixing the constituents and when the concrete is wet (Lamond and Pielert 66).
Procedure
A sample of concrete was taken from the wheel barrel. The sample taken was within a quarter of an inch.
A steel slump cone with top diameter of 4 inches and bottom diameter of 8 inches and 12 inches high was used to carry out the test.
The cone was placed on an impermeable solid ground with a level base and filled with fresh concrete in three equal layers
Each layer was rod 25 times in order to ensure total compaction
The third layer was leveled off with the top of the cone.
After adding all layers, the cone was carefully lifted up in order to leave a heap of concrete that settled slightly.
The steel slump was then placed on the base of the test to act as a reference. As the concrete settled, the differences in levels between the top of the cone and the top of the concrete was measured and recorded. The distance from the middle of a slump to the top of the cone was measured that represented the slump of the concrete. See figure 1.
Figure 1: Slump test
Compressive Strength Test
The compressive strength test for concrete helps in determining the strength of concrete. Concrete has many durability and mechanical properties that meet different purposes that the material performs in construction. Engineers use compressive strength of cement to design various structures. A compression testing machine is used to determine the compressive strength of concrete (Lamond and Pielert 136).
Procedure
The compression testing machine was checked to ensure it was clean of any debris. A clean apparatus allows equal distribution of compressive load acting on the concrete cylinder and prevents any errors that might interfere with the actual results.
The concrete was poured into cylindrical molds to form concrete cylinders
The concrete cylinder was placed in a curing room for 24 hours after it was poured in molds. The mold was then observed for one week in order to ensure they had totally cured
Moisture testing was done to concrete cylinders in the curing room in order to determine the level of dryness.
The cylinders were then placed in a metal cap with rubber lining for effective distribution of load throughout the cylinder. The metal cap was placed on both sides of the cylinder in order to make contact with compressive machine.
The metal caps were then placed in the middle of the machine, and the machine turned on. See figure 2 below.
A constant load was maintained throughout until cracks were observed on concrete that eventually broke the cylinder a clear indication that the concrete had failed.
The maximum compressive load of each cylinder was recorded. Compressive strength was acquired from dividing maximum compressive load before the concrete failed with the cross-section area of the cylindrical concrete specimen.
Figure 2: Compressive Testing machine
Modulus of rupture
The modulus of rupture of concrete us used to test the tensile strength of concrete beams. The strength depends on the length of the concrete beam. The test aims at calculating test distributions that cause cracking of the concrete beam prior to application of maximum load. It is calculated from the formula:
k = PLbd2 ……………………………………………….eq. 1
Where:
P – Load applied
L- Length
b – Breadth of the beam
d – Width of the beam
Procedure
The beam measuring 6 by 6 by 25 inches was used to calculate the modulus of rupture of concrete.
The concrete was poured into a rectangular mold and left to cure for one week.
Two lines were drawn three inches from each edge of the beam. A new line was marked after every 6 inches making a total of 36 lines drawn on each side of the rectangular mold. Additionally, there were two three by 6 inches rectangles drawn on each side of the specimen.
The rectangular concrete specimen was placed into a compression machine, a different from the machine used during compression strength test as shown in figure 3.
The specimen was centered in the machine in order for the lines drawn on the specimen to line with the semi-circles located on the device. The concrete specimen was carefully placed in order to allow for proper distribution of loads in all locations of the block.
The metal caps of the machine were lowered to allow the rectangular specimen fit correctly on each side of the machine. The dial display was zeroed, and load applied at a rate of 2000 pounds per minute.
The load was applied until the specimen started cracking. The maximum capture load was observed and recorded.
The modulus of rupture was calculated using the formula in equation 1 above.
Figure 3: Setup for the modulus of rupture test
Modulus of elasticity
The modulus of elasticity (E) was tested using a cylindrical concrete mold measuring 6 inches in diameter and height of 12 inches. It is calculated by dividing stress by strain.
E = τΔl …………………. Eqn. 2
Where: τ – Stress
Δl-Change in length Procedure
A 6 b y 12 inch concrete cylinder was molded the used to test the modulus of elasticity for concrete.
The testing device was screwed into the concrete cylinder.
The device was first screwed on the top of the cylinder and later on the bottom in the central position.
After the set up the test, equipment were placed in the compressive machine as shown in figure 4.
The machine was first set to full load and later adjusted to moderate load of 2000 pounds.
The compressive machine reached 10% and 40% strength levels as a close look was made to the device and the concrete specimen to observe any change.
The change in length of the specimen was recorded at each percentage levels above, and the test continued.
The strain was calculated by multiplying the change in length with 0.0001. With the amount of load applied known, the modulus of elasticity was calculated using the formula in equation 2.
Figure 4: Modulus of elasticity test setup
Split tensile Stress
Split tensile stress was determined by testing a concrete cylinder measuring 6 by 12 inches. It is calculated from the equation:
T=2Pπld ………………………………… 3
Where:
P – Load applied
l- Height of the cylinder
d – Diameter of the cylinder
Procedure
A steel cylindrical mold was used to make the cylindrical concrete specimen measuring 6 inches in diameter and 12 inches high
The cylindrical specimen was placed in the compressive testing machine
A metal bar wad centered at the top of the cylinder, and the load lowered to fix the metal bar to the machine as shown in figure 5.
The compression machine was automatically controlled using a computer where load values were observe on the screen.
The computer level was zeroed, and load applied using the split cylinder test.
The load was applied until the specimen split into two parts. The Split tensile stress was calculated from equation 3.
Figure 5: Split tensile stress test set up
Curing procedures
After the finishing the above tests, the concrete mix was poured into different molds for curing. Curing was done in order to preserve the concrete for future experiments. The molds were smeared with oil on the inside part in order to prevent concrete from sticking to the sides of the mold. The concrete mix was poured into the mold. The concrete mix was compacted into the mold to eliminate any air. The compacting rod was dropped 25 times for circular molds and 36 times for rectangular molds to ensure total compaction of concrete in the mold. A metal plate containing group number was placed on top of the mold. The compacted concrete mix was allowed to stay in molds for 24 hours. The molded specimens were then removed from the molds and taken into a curing room where they would stay for 28 days.
Conclusion
The lab results contributed more in understanding the mechanical properties of concrete. It was realized that the type of material and the mode of mixing used plays a critical role in determining the strength of a particular concrete mix. The type of cement water ratio used to make concrete mix determined the compressive strength and the curing time. Samples with high water-cement ratio took long to cure and were the strongest. Additionally, cross-sectional areas of molds used determined the curing time of the concrete mix, as well as the strength. 4 by 8 inches molds had stronger compressive strength with similar water-cement ratio compared to the 6 by 12 molds. Compressive strength of the material is inversely proportional to its cross-sectional area, the small the area the stronger the concrete.
On the other hand, the lab test revealed that the air-entrained concrete recorded lower tensile and compression stress. Additionally, air-entrained samples had lower modulus of elasticity compared to normal samples when made up from high cement-water ratio. The air-entrained concrete mix recorded lower strength because the voids left in the concrete reduce bonding causing weak points. Finally, the coarse and fine aggregate concrete mix recorded varying results in terms of tensile and compressive strength. Concrete mix made from fine aggregate was the strongest in compression, but poor in tension compared to sample of coarse concrete. In conclusion, the strength of concrete mix depends on water-cement ratio, size of aggregates, and compaction rate.
Works Cited
Lamond, Joseph F, and J H. Pielert. Significance of Tests and Properties of Concrete and
Concrete-Making Materials. Philadelphia, PA: ASTM, 2006. Print.
Kerkhoff, B. “ Benefits of air entrainment in HPC”. HPC Bridge views, 23, 2002.
National Precast Concrete Association. Concrete sampling and testing. Tech Notes. 2013. Web
http://precast.org/wp-content/uploads/2011/05/TechNote_Concrete_Sampling_and_Testing.pdf
Prowell, Brian D, Jingna Zhang, and E R. Brown. Aggregate Properties and the Performance of
Superpave-Designed Hot Mix Asphalt. Washington, D.C: Transportation Research Board, 2005. Print.