Investigating Glue Essay
To recycle the bad protein food by reproducing glue
Have you even thrown some food because it becomes bad? Do you think it really waste money? Do you want to make them become useful again? If you do, our experiment will show you how to do and everything about it.
Heater, measuring cylinder Ã¯Â¿Â½2(250ml50ml),
pH paper,beakerÃ¯Â¿Â½2(300ml500ml),glass rod, spoon
skim milk, vinegar
The sticking properties of different proteins in daily food are being investigated in our experiment.
Casein in dairy products and textured soy protein (TSP) in soybean products are abstracted out by precipitation in acid. The samples are then neutralized by carbonate and undergo a series of stress tests to compare the strength of our reproduced protein glues with commercial products.
The basic principle of the sticking properties of protein glues is the ionic attractions and the Van der Walls attractive force generated by the protein molecules. Protein molecules are highly folded, resulting in a great contact surface area and exposure of the hydrophobic bonds. When two surfaces of substances like wood or paper are held together by protein, linkages are formed in between the molecules, and the two surfaces are stick together and are difficult to separate.
We expect the result the casein in milk and textured soy protein in soybean milk have comparable sticking strength as starch contained in commercial glue. The significant advantage of the production of our protein glues is that proteins in expired food can be recycled and reused to make the useful glue. The glue produced is also not toxic or harmful to the environment.
1)The history of glue
The earliest evidence of use of glue can still be observed in the cave paintings made by Neanderthal ancestors in Lascaux, France. These early artists wanted their work to last and mixed glue with the paint they used to help the colors resist the moisture of the cave walls. Egyptian artifacts unearthed in their tombs show many uses of glues; perhaps the most striking are the veneers and inlays in wood furniture, which was made using glue as early as 3,000 B.C. The Egyptians also used glue to produce papyrus. Greek and Roman artists used glues extensively; mosaic floors and tiled walls and baths are still intact after thousands of years.
Around 1750, the first glue or adhesive patent was issued in Britain. The glue was made from fish. Patents were then rapidly issued for adhesives using natural rubber, animal bones, fish, starch, milk protein or casein. As we can see from ancient and medieval records, fish glue was both a common and important adhesive for many special applications; adapted by artists, it was used from the time of ancient Egypt to twentieth-century France, in painting media, coatings and grounds, in the gilding of illuminated manuscripts, and in pastel fixatives.
2)Theory of milk glue
Casein is the principal protein found in cow milk (about 3%) from which it has been extracted commercially for most of the 20th century. It is responsible for the white, opaque appearance of milk in which it is combined with calcium and phosphorus as clusters of casein molecules, called micelles.
The major uses of casein until the 1960s were in technical, non-food applications such as adhesives for wood, in paper coating, leather finishing and in synthetic fibers, as well as plastics for buttons, buckles etc.
The first step in making acid-precipitated casein is acidification. Mineral acids or organic acids can add to the skim milk; or the milk is allowed to sour, in which case lactic acid, produced by fermentation of lactose, is the effective precipitant. The precipitated curd is then drained, washed, press to remove water, milled, drill, and ground. Solutions of casein in alkalis (with enough of the protein to give a suitable viscosity) can be used as glue.
Such glue compares favorably in strength with animal glue on drying the protein forms numerous hydrogen bonds with the cellulose in paper and with itself, so it can stick woods together, but it is not water-resistant. Resistance to water can be imparted to casein glue, however, by modifying the simple formula of casein in alkali; these improved casein glues are widely useful in industry. Prepared casein glues are sold in the form of dry mixtures, which need only the addition of water before use.
They are commonly composed of casein, lime, and a number of alkaline salts. Various chemicals have been used to improve the resistance to water, and many colloidal materials with adhesive properties can be mixed with casein to modify the properties of the resulting glues. It has thus been possible to adapt casein glues to a variety of specialized applications. These glues are used in the woodworking industry, in gluing paper, and in many other fields.
Ã¯Â¿Â½Preparation of milk glue
1) 250cm3 of milk and 50cm3 of vinegar (about 5% ethanoic acid) were added into a beaker.
2) The mixture was heated slowly and stirred continuously until curds were observed. (Caution: Heater is very hot, temperature of mixture should not be more than 60Ã¯Â¿Â½C)
3) Curds were allowed to settle to the bottom for about 10 minutes.
4) The heated mixture was filtered.
5) The curds were squeezed to remove liquid.
6) The curds were washed with little volume of water and squeezed again.
7) The curds were stirred with solid sodium hydrogencarbonate (NaHCO3) gradually and monitored pH by pH paper until pH became slightly alkali.
Ã¯Â¿Â½Testing of adhere strength of glue
1) The glues were used to stick two plywood together, a the plywood at downside , with contact surface of 20 cm2
2) Two samples were made for each glue and one sample of starch glue was made as control.
3) The stack plywood was pressed by 0.8kg mass and allowed to dry at dry place for 2 days .
4) The plywood was set above the ground.
5) 0.5 kg Test mass was added gently each time until the masses drop.
6) The maximum mass of the glues that can afforded were recorded.
7) The plywood was cut into 4, which contact surface was decreased 4 times, and the above tests were repeated.
If I need to choose one of my family members, I may prefer to write about my superhero in my life that is my beloved father. Actually in my mind, I had three persons that always be my superheroes in my life. They are my elder sister that I call â€˜Alongâ€™, my beloved mother and my beloved father. Each of them has their own achievement in their life that I think I should be proud and respect to them. Besides that, these three person are always be the person who always supporting me from my back when I need somebody to be my shoulder beside my closed friend. My father might not be the superheroes such like Superman, Spiderman or Batman but my beloved father are always be the great superhero in my life. There are the reasons why I choose my beloved father to be my super hero and the person I think I need to describe about.
> First and foremost, I want to describe about the characteristics of my father that I love so much. Everyone in this world has their own father and surely they also have their own opinion about the characteristics of their beloved father. So do I, I also has my own opinion about the characteristics of my father that I impressed from I am kids until who I am today. He is an open-minded and a patient person because if I want to share anything to my father, he will listen carefully on what I want to talk about and after that he will try to give the best solution to me to solve the problem. After that, he is good disciplinarian because my father loves his children but he does not let we get away with murder. He strongly disapproves of his childrenâ€™s misdeeds, using tough love to prove a point. He does this through the power of his words, not his fists. Furthermore, he is a firm father too because when he set a rule, he still give we a little freedom to break it with a rational reasons.
In addition, from my observation my father has a great characteristic to be a good leader to my family, his friends and students. I cannot deny about it because I heard with my own ears what my fatherâ€™s friends and students talking about his attitude in work and everything are positive criticism. Actually, I am proud to be his daughter because there too many achievement that my father achieved in his career. Sometimes I feel confused why my
fatherâ€™s friends said that I need to be proud with my own father. And now, I knew the reasons why and I agreed with them. The achievement that my father had achieved in his life really can inspire me to be like him.
He is really hard working to get what he wants to achieve in his life. He really makes me feel that my father is a great person at my eyes. Furthermore, he is a discipline person in his work. If my father had nothing to do on that day, he will start to finish his work. My father will try to finish his work according to the plan he created. My father is a humble person too because the first point I see is my father not teach my family to live in clover, although in fact he was able to provide it. Then, my father still be himself even he had a great achievement in his life and he do not like to use his rank that he has in his daily life or anything. For him, the rank will bring us nowhere and it was just the rank.
Last but not least, I really impressed with the history of life of my beloved father. My father actually are not comes from an easy family but with his hard working and perseverance in study can helps he to improve the standard of living of his family until now. That is why my father really focused about the education in our family. It is because my father always said that without education, we will go nowhere. That was his principle in life. My father does not want his own family not have an education even we cannot get the best achievement or a good career. He also wants to give the best to our family and I realized about that I really impressed to make my father as the role model that I can emulate in my life.
For conclusion, we need to give our best in anything we do in this life. Besides that, we need to know on how to appreciate the kindness and others person around us especially our beloved father. Their sacrifices cannot be valued with a million dollars of money or the diamonds in this world. Make our father as our superhero are the best choice because there can be good role model to us in life.
A true friend
A friend who helps out when we are in trouble is a true friendâ€”unlike others who disappear when trouble arises. Friends are one of most important things in our lives. Unfortunately we have a few real friends. I have a lot of friends- girls and boys. It doesnâ€™t matter what they are. They have to be my real friends. He or she has to be good and reliable. It doesnâ€™t matter how he or she looks like. He or she has to be responsible and helpful. I think these people are one of the best people in the world. If she or he is attractive and sensitive it will be wonderful! Just like me! But we have to be good with our friends who havenâ€™t got character like this. Every man has features which he doesnâ€™t like. We shouldnâ€™t forget that we are people, too. Iâ€™m sure that if we are good with people we will have more and better friends. I have a friend named Nobin Jacob who went to the High School â€“India (September 18, 2001) .
He did not have to work because he parents paid for her school and all his expenses. All he had to worry about was studying and doing his homework. Nevertheless, instead of using the time wisely, he would always put off doing his schoolwork by saying that there is enough time to do it later. Moreover, almost ever every afternoon he watched television and talked on the phone with his friends. Still, he preferred to study after eight oâ€™clock at night, but this was the time his friends wanted to go out. Unfortunately, he would hardly ever do his homework; thus, his essays were also late. After Nobinâ€™s first year at the school, his grades seemed to get worse and worse. What do you think would happen if Elizabeth would have to work and pay her own tuition? Do you think it would change her behavior toward school? Finally, I concluded that students who pay their own tuition are more likely to do well in school.
First and most importantly, I think it is proper time management that effects good performance in school. Let us look at the students who do not have to pay their own tuition, so they do not have to work. Because they have a lot of free time after school, they think that there is enough time to do their homework later, so they do not even bother to think about it and plan when to do it. For example, think about the time that some of them waste by watching their favorite TV shows, or by playing games on the Internet. This time could be used for doing math problems or for starting to write an essay, which could be due in a week. These students tend to put things off for later.
On the other hand, because students who work while going to school have a limited time for studying and doing homework, they have to plan their time for the future, so they do not put themselves behind other classmates. They see time as time blocks, so they plan their work ahead. For example, if they know that they are working tomorrow, and their homework is due in three days, most likely they would start doing their homework today because they realize that tomorrow they will be too tired after work to do their homework. Indeed, time for work and school can be hard to juggle, but it helps students organize their time, so there is enough time to do the assigned homework or to study. In fact, they are paying for school with their own money; thus, they do not want to waste the opportunity to do well in school. For this reason, students who work and go to school at the same time value time more than students who do not work; working students must know how to organize their time to
Every human has their own needs and wants. Needs like food, home, clothes and so on are very significant for each and every human. Besides all those necessity, every human also needs to have a friend. Friends are one of most important things in our lives. I think these people are one of the best people in the world. Friends are people that you can rely on. Some name their friend as close friend. This happens when a particular friend, be concerned with you more like a family and vice-versa. You will get to know each other deeply. I have a lot of friends- girls and boys. But they are not my close friend. I can trust all of them though. They might be nice and friendly to me but they might not understand the real me. My close friend should be someone who knows every single thing about me, loving and is someone a part of me.
Like everyone else, I also do have a friend; close friend. My close friendâ€™s name is Tina. There is nobody like her who had changed my life dramatically. I first met Tina at my uncleâ€™s wedding. I still remember she was dressed in a very astounding dress and was the center of attraction. I was very jealous of her back then. After having dinner, the dance floor was opened. I was afraid to ask her to dance with me and so was she. After few minutes, she walked towards me and she asked,â€ Youâ€™re Uncle Marikâ€™s daughter right?â€. I replied yes. I asked her how she knows me. Then she said that her father and my father are childhood friends. And thatâ€™s how we started talking to each other. We danced all night long. Tina is actually from Penang. Since it was too late that night, she and her family stayed over at my place. We got to know each other better now.
I was sad when she had to go back the next day. Although we have just met, but I feel very happy having her by my side. After a few days, her mother called my mother to ask permission if Tina can stay with
Dengue fever also known as breakbone fever, is an infectious tropical diseasecaused by the dengue virus. Symptoms include fever, headache, muscle and joint pains, and a characteristic skin rash that is similar to measles. In a small proportion of cases the disease develops into the life-threateningdengue hemorrhagic fever, resulting in bleeding, low levels of blood platelets and blood plasma leakage, or into dengue shock syndrome, where dangerously low blood pressure occurs.
Dengue is transmitted by several species of mosquito within the genus Aedes, principally A. aegypti. The virus has four different types; infection with one type usually gives lifelong immunity to that type, but only short-term immunity to the others. Subsequent infection with a different type increases the risk of severe complications. As there is no commercially available vaccine, prevention is sought by reducing the habitat and the number of mosquitoes and limiting exposure to bites.
Treatment of acute dengue is supportive, using either oral or intravenous rehydration for mild or moderate disease, and intravenous fluids and blood transfusion for more severe cases. The incidence of dengue fever has increased dramatically since the 1960s, with around 50â€“100 million people infected yearly. Early descriptions of the condition date from 1779, and its viral cause and the transmission were elucidated in the early 20th century. Dengue has become a global problem since the Second World War and is endemic in more than 110 countries. Apart from eliminating the mosquitoes, work is ongoing on a vaccine, as well as medication targeted directly at the virus.
Typically, people infected with dengue virus are asymptomatic (80%) or only have mild symptoms such as an uncomplicated fever. Others have more severe illness (5%), and in a small proportion it is life-threatening. The incubation period (time between exposure and onset of symptoms) ranges from 3â€“14 days, but most often it is 4â€“7 days. Therefore, travelers returning from endemic areas are unlikely to have dengue if fever or other symptoms start more than 14 days after arriving home.Children often experience symptoms similar to those of the common cold and gastroenteritis (vomiting and diarrhea) and have a greater risk of severe complications, though initial symptoms are generally mild but include high fever.
The Causes And Effects Of Cramming Essay
Every Day Student goes to school and university, and they are learning new material and new assignments. Some students study every day what they learnt, but some students let the studying until they have exams or something to do. Thatâ€™s called cramming. What is the meaning of cramming? , and what are the causes of cramming? , and what are the positive and negative effects of cramming? Cramming is the practice of trying to study a large amount of class material in a short period, typically the night before an exam, test, or quiz. It is often done by students in preparation for upcoming exams .Students cram for a number of reasons including fear of failure because of disabilities, over with little or no time to study. This can happen to students with jobs, family obligations, or who may be involved in too many extra-curricular activities. Cramming may increase levels, low motivation to study on a regular basis well before time for tests, and underachievement. Cramming is often discouraged by educators because the hurried coverage of material tends to result in poor retention.
There are various causes of cramming. First, the students do not follow a fixed time for study because they donâ€™t schedule their studying. Second, studentsâ€™ donâ€™t take notes of important points given in the lecture, so they donâ€™t study well for their quizzes and exams. Third, the students did not revise the material from time to time, so they forget the material. For example, a student took new topics in math. He should not revise it only in the day of the exam, but he should revise it from time to time. Also, another cause of cramming that the student feel boring of studying during the semester, so he/she will leave studying until the exams start. Cramming has a lot of negative and positive effects. There are variable negative effects of cramming. First, the person uses the memory instead of understanding the concepts and getting benefit from the material.
Write something about yourself. No need to be fancy, just an overview.