Polymorphisms of Crystalline Solids :: Chemistry Engineering Science Essays

Polymorphisms of Crystalline Solids Polymorphism is the phenomenon where a compound can precipitate to form numerous crystal structures. Due to space and time limitations, we have decided to confine the scope of this paper to only include polymorphisms of crystalline solids and not include polymorphisms associated with DNA and genetic related topics. It is important in many areas of technology, that people are aware of the presence of polymorphisms and the properties of the different polymorphisms. The different crystalline structures each have different physical properties, which can change the use of the chemical. The physical properties that may differ from one polymorphism to another include: solubility, density, melting point and even color. One of the variables that affect the crystallization process is the solvent that is used in the precipitation. The solvent may cause less stable polymorphisms to form instead of those that are more stable. Predictions can be made as to which polymorphism wil l be formed based on the solvent and its properties. The mixing conditions also have an affect on the formation of various polymorphisms. (Meyerson) Different polymorphisms can also be formed by manipulating the solute concentrations, flows rates, and equipment configurations. Research involving polymorphisms is becoming increasingly important to the pharmaceutical industry due to the number of pharmaceuticals that are prone to polymorphisms, patents on certain polymorphisms, the differing bioavailability of the polymorphisms and the differing effects of the polymorphisms on the body. (Meyerson) During the 1970’s, G.M.J. Schmidt coined the term crystal engineering and defined it as predicting the crystal structure of solid-state organic molecules (Sharma). In 1989, G.R. Desiraju revised the meaning as the â€Å" ‘the understanding of intermolecular interactions in the context of crystal packing and in the legalization of such understanding and the design of new solids with desired physical and chemical properties’ † (Sharma). Crystal engineering has grown to encompass the study of the hardness and color of solids, nanotechnology, protein receptor binding, pharmaceutical development, and polymorphisms (Sharma). Crystals are used in many areas of science, pharmaceuticals, and materials engineering. Crystals differ from many other organic and inorganic materials because of their ability to form polymorphisms.

Ernie Breaks Essay

Sometimes expectations are too big to satisfy, even though you try your very best. It would be wrong to raise expectations to a level that cannot be met. You are scared that you might disappoint the people you have closest. Therefore you try to hide yourself and your insufficiency. This is just one of the things Cara deals with in the story, Ernie Breaks, written by Genevieve Scott. The short story is told through the eyes of Cara. Cara has just finished fourth grade, and her mother wants to reward her for that. Therefore she brings Cara and Caras brother Jed to a pet store. Here they decide to buy a turtle, which Jed and Cara have to share. They call the turtle Ernie. One day when Cara comes home from school, Jed is maltreating Ernie. This makes Cara very sad and she wants to show her mother what Jed had done and show that Ernies tank is very messy. She ends up loosing Ernie, as he falls to the ground and dies. The characters get described in an indirect way, where the reader has to draw conclusions from the way the characters act and how Cara explains them from her point of view. An example of that is where Jed is described: â€Å"He goes in there with his friend Toby everyday after school to play records and ignore me. This means that Jed also doesn’t help me with my math homework like Mom made him promise, so I am terrified that I’ll fail or get moved into retard room†1. This is a good example of the indirect characterization, as this quote shows us that Jed is a brother, who does not worry very much about his sister. Firstly, he ignores her and secondly, he does not help Cara with her math, even though he promised. In addition you can see that Cara is very bad at math and needs help to get better. Throughout the short story Cara gets seen very considerate, especially around Ernie: â€Å"[†¦], if I say anything though, I’m afraid I’ll start to cry †2. The fact that she nearly starts to cry, because Jed and his friend, Toby, are teasing Ernie, means that you get the impression that Cara is a very considerate and emotional person, especially when something happens to Ernie. This can have something to do with that she feels safe around Ernie. Furthermore Cara looks very much up to her elder brother Jed. This can be seen where Cara had got in trouble for painting on the girl from her class’ shirt: â€Å"He’ll at least think its cool that I got in trouble†.3 The fact that Cara thinks that getting in trouble is not so bad,  because her brother will think she is cool, shows us that Cara looks very much up to her brother. As well she uses the same words as Jed: â€Å"[†¦] get moved into the retard room†. In the beginning of the story we get told that â€Å"Retard room† is a word that Jed uses. Therefore we are informed that Cara uses the same words as Jed. The main theme in this short story is family relationship and about expectations, you have defined for each other. Observing the behavior of the characters, it can be seen that the main theme, family relationship, comes to expression through the characters in the way that the expectations they have for each other gets broken and they try to hide their insufficiency. This can be seen in all three characters. In the start Cara tells us about her mother and how she is trying to stop smoking with help from Quit4life, but in secret buys cigarettes from a pharmacist called Ernie Sherman: [†¦] Ernie Sherman, the pharmacist where Mom buys her cigarettes because she won’t run into anyone from Quit4life†4. Here it is obvious that either herself or the people from Quit4life expect her to stop smoking. Still, she does it secretly and in that way she tries to avoid losing face. She does that to hide her incompetence . The same behaviour is visible in Cara. She is expected to take care of Ernie, but ends up killing him by dropping him on the floor: â€Å"I jump backwards like Valerie Calorie and Ernie flips up off my palm and crashes off the edge of the tank and onto the floor†.5 Afterwards, she pretends having accomplished the expectations that is set for her by not telling her mother the truth about what happened. The short story also explains the expectations for Jed. He is – as well as Cara – supposed to take care of Ernie, but ends up maltreating him to play cool in front of his friend: â€Å"Jed is holding Ernie over the turntable. He puts him down shell-first and then puts his index finger on his belly.†6 Genevieve Scott uses in this short story symbols. The turtle in this short story symbolises Cara and what she has experienced, where she has to lock herself in a shell. An example of that is where she has to have a math test, and she does not know how to do it an d draws a picture of Ernie instead. Besides, she does not want to show Valerie her results: â€Å"I take Valerie Calorie’s from her, but I don’t give her mine.†7 Here you can see that she is embarrassed and therefore she wants to lock herself in a shell to protect her. Moreover she hits back against the people who do something bad to her like Ernie does when he experiences something bad: â€Å"I grab the black magic  marker from inside my desk and swipe it across her yellow sweater†8. Here you can see that she does not put up with people making fun of her in the same way Ernie does not put of with being maltreated. Therefore there can be drawn parallels between Ernie and Cara. At the end where Ernie dies, something dies inside of Cara as well: â€Å"I don’t understand why we have to learn about broken numbers. If something is broken, it’s wrecked and useless anyway. If it’s not your fault that it’s broken, you usually don’t need to care about it†9. If you interpret this quote, you can see that Ernie’s shell symbolises the shell Cara has to protect herself with. When Ernie’s shell breaks, Caras shell breaks as well, and as Cara says,† when something is broken, it’s wrecked and useless†. So we can therefore conclude that when Ernies shell breaks and he dies, Cara feels wrecked and useless. Overall we can conclude that Genevieve Scott really has been capable of telling a story with focus on family relationship with the short story â€Å"Ernie Breaks†. Genevieve Scott has throughout the story used a first person narrator, writing from Caras point of view. This has made it easy for us as reader to understand what Cara thinks. The story is furthermore in possession of an indirect characterization, and we learn about the characters through their actions.

West and East 5 Main Differences in Approach towards Education

‘East is East, and West is West, and never the twain shall meet’, Rudyard Kipling wrote, and despite world getting more and more homogenous, West and East are still different. Due to difference in history, prevailing religions, political regimes and so on, and these differences are clearly seen in Western and Eastern approaches to education. 1. Creativity vs. Effort Western educational systems put stress on the ideas of creativity. Of course, the system being a system means that many things are unified, but still, it usually does its best to promote individual approaches to different students. Eastern education is all about effort and struggle – no thing is hard if you practice enough. Therefore, children are given enormous amounts of homework and are taught to work hard – that’s why Asian students are often much more productive than their peers when they get into more relaxed Western educational institutions. 2. Participation vs. Reception Western education moves further and further along the road of turning students into full-fledged participants of education process. They are encouraged to ask questions and dispute with their teachers, to think critically. In the East, students are the recipients – they submit to the authority of teachers and the process itself is far less interactive. 3. Special needs: Inclusion vs. Separation Western education makes great efforts to include children with special needs into the general mass of students – they tend to be taught together with normal children or at least it is considered to be their fundamental right. In the East we generally see a diametrically opposite approach – children with disability are almost always taught separately from the rest, and it isn’t considered to be discriminatory, just logical. 4. Individualism vs. Conformity Rugged individualism has always been one of the most characteristic features of Western societies and it is only natural that Western educational systems reflect it. Individuals are considered to be much more important than groups; which means that Western students are far less afraid of vocalizing their opinions and making mistakes – these are considered to be the natural part of personality development. Eastern societies tend to be much more collectivistic, and collectivism breeds conformity – in order to succeed in a group, an individual has to conform to its values, principles and opinions while avoiding criticism and saving face whenever possible. 5.  Fulfillment vs. Result The popular idea in current Western education is that students have to find fulfillment in their studies – that is, study what they like and how they like in order to find their place in life. Eastern education, however, aims at making people more productive – both for themselves and the society in general. Children are being sent to cram schools from early age, spend long hours studying in order not to lose out to their peers – in other words, education doesn’t aim at being fun. When all is said and done, we should remember that the word ‘versus’ here is for decoration only. These are not opposing views; these are just different approaches to one and the same thing.