nuclear reactions essays

nuclear reactions essays Chemical reactions are the heart of chemistry. People have always known that they exist. The Ancient Greeks were the first to speculate on the composition of matter. They thought that it was possible that individual particles made up matter. Later, in the Seventeenth Century, a German chemist named George Ernst Stahl was the first to postulate on chemical reaction. He said that a substance called phlogiston escaped into the air from all substances during combustion. He explained that a burning candle would go out if a candle snuffer was put over it because the air inside the snuffer became saturated with phlogiston. Stahl also said that phlogiston will take away from a substance's mass or that it had a negative mass, which contradicted his original theories. In the Eighteenth Century Antoine-Laurent Lavoisier, in France, discovered an important detail in the understanding of the chemical reaction combustion, oxigine (oxygen). He said that combustion was a chemical reaction involving oxygen and another combustible substance, such as wood. John Dalton, in the early Nineteenth Century, discovered the atom. It led to the idea that a chemical reaction was actually the rearrangement of groups of atoms called molecules. Dalton also said that the appearance and disappearance of properties meant that the atomic composition dictated the appearance of different properties. He also came up with idea that a molecule of one substance is exactly the same as any other molecule of the same substance. People like Joseph-Lois Gay-Lussac added to Dalton's ideas with the postulate that the volumes of gasses that react with each other are related. Amedeo Avogadro also added to the understanding of chemical reactions. He said that all gasses at the same pressure, volume and temperature contain the same number of particles. This idea took a long time to be accepted. His ideas lead to the subsc ...

Friedrich and German Romanticism essays

Friedrich and German Romanticism essays The period of German Romanticism broke the individualist and rationalistic thinking of the Autklarung, advancing aesthetic ideals that transcended reason and exalted art. The flourishing of this period can be characterized in numerous ways, one of which is through a glimpse in the life of German Romantic artists such as the famous landscape painter Caspar David Friedrich (see appendix 1). To a large extent, the content and abstraction of Friedrich's works mirror the Romanticist idealism in Germany during his time, as reflected in his compositions such as the allegorical oil paintings Wanderer Above the Sea of Fog (1818) and Stages of Life (1835) (see appendix 2 and 3). In these works, the artist took a great deal in transforming landscape paintings from objectivism to an intense and emotional depiction of man, nature and the metaphysical. Meanwhile, the dynamism of his life as an artist is as intense as his works of art. On one hand, he suffered from considerable criticisms and during his time, he was not able to gain the wide approval the public. On the other hand, he was also praised by many of his contemporaries in the Romantic Era due to his artistic, philosophical and aesthetic treatment of his works. In any case, he still remained as one of the most staple and distinguished figures of the Romantic Movement in Germany. This paper further examines on these contexts in the subsequent sections. A discussion on the artistry of Friedrich can begin no less than through a brief discussion on his biography. In essence, Friedrich had a life replete with both triumphs and adversities; his early life began in a series of tragedies and it ended with him being half-mad. Born on September 5, 1774, in Greifswald, Swedish Pomerania, on Germany's Baltic coast, Friedrich was the sixth out of the ten children, raised in a strictly Lutheran family (Collins). Unlike the trouble-free childhood experi...

E-Waste Environmental and Workers issues Essay Example | Topics and Well Written Essays - 1000 words

E-Waste Environmental and Workers issues - Essay Example It also presents the brighter side of upgrading e-waste or called e-cycling. Jim Puckett et al (2002) define electronic waste or e-waste as the increasing scope of electronic devices ranging from huge appliances in different households such as refrigerators, air conditioners, mobile hand-held cellular phones, personal stereos, and consumer electronics up to computers. E-waste is dangerous. E-waste consists of 1,000 various substances in which most of these are toxic and contributes to the gravity of pollution when disposed. Some of these toxic chemicals are (1) lead and cadmium found in circuit boards, (2) lead oxide and cadmium in cathode ray tube (CRTs) of monitors, (3) mercury in switches and flat screen monitors, (4) cadmium in computer batteries, (5) polychlorinated biphenyls (PCBs) in old capacitors and transformers, and (6) brominated flame retardants on printed circuit boards, plastic casings, cables and polyvinyl chloride (PVC) cable insulations. (Puckett et al, 2002) E-waste is produced at alarming rates due to obsolescence. The fast paced development of technology resulted to for many gadgets, hardware systems, computers to be replaced in a short span of time. For example, a computer system which can last for five years or so is replaced in a year or two because of increasing technological developments that produced new and updated products. Also when electronics and other devices break down, the cost of repair can be higher than buying new ones. The high rates of obsolescence increase the volume of waste as compared to consumer goods like food. (Puckett et al, 2002) Puckett et al (2002) discuss that e-waste is produced by three (3) major sectors in the United States: (1) individuals and businesses, (2) large businesses, institutions, and governments, and (3) original equipment manufacturers. For the first sector, the equipments most frequently disposed by households and businesses are computers. The primary reason for this is not because of

Film Review Movie Example | Topics and Well Written Essays - 1250 words

Film - Movie Review Example The theory of social exchange is well demonstrated in the movie the color purple. It is a movie with different characters and demonstrates love, hatred, racism, poverty and sexism. There is a direct link between the theory and the movie as explained below. Social Exchange Theory In-depth Major reason for business set up to any entrepreneur is to make profit. In order to make profits one need to reduce costs and maximize returns. Thus the concept of cost benefit analysis emerges. One need to weigh the cost incurred in relation to benefits derived. In case the cost exceeds the benefits a loss occurs and thus the business is no longer profitable. The same concept applies in social exchange theory. The benefit derived in a relationship is a reward. A reward may be in form of closer ties, promotion at the work place, enhanced relationship and support. In a bid to benefit from these virtues one need to cultivate a culture acceptable with a view of morerewards. An idea that depicts approval is the one that ends up being repeated and vice versa. Aclient who returns for more service is the one has been satisfied with the service provided before. Thus it can be demonstrated whether a particular behavior is bound to be repeated by analyzing degree of returns (approval level) or punishment (disapproval level) as a result of the interaction. In order to demonstrate this following formula is applicable: Profits = interaction rewards –interaction costs. ... The Color Purple This movie took place in the early 1900s. It was acted in South –United States on America. It is a movie that’s demonstrates intense struggle faced by a young African American girl known as Celie Harris. The girl was abused by her father when she was young. By the time she was fourteen she had two children by her ‘dad’ (Leonard Jackson). Leonard forced her daughter Celie to be married by a young wealthy widower known as Albert Johnson. This clip shows how Albert treats Celie like a slave demonstrating how he loathed her. Despite the beating that she received Celie was forced by Albert to make a clean up of his household and look after his disobedient children. A sister to Celie (Nettie) at one time gives them a visit and the movie shows a brief change of environment as the sisters happily conversed.Celie is thrilled as her sister offers to teach her how to write. But the experience is short-lived as Albert tries to make immediate affectiona te moves to Nettie who declined and was thrown out. Celie is promised by Nettie to constantly be receiving letters from her and saying that only death can keep them from it. In another scene a friend to Albert known as Shug Avery comes to live with Albert's family. Shug describes Celie as an ugly woman but despite this their relationship is cordial. At once instance Celie and Shug engage in sexual intimacy. Apart from strength gained from ShugCelie’s life is strengthened by Sofia who is Albert's daughter in law. Sofia is married by Albert's son Harpo. Just like Celie Sofia had faced a hard life with men. But this woman demonstrates her high hearted nature a move taken by surprise by Celie. Sofia's high spirit resulted to her failure in life. At one time she is beaten and

Japanese Art Essay Example for Free

Japanese Art Essay For the GOY* project, I chose to visit The Pavilion of Japanese Art in the Los Angeles County Museum of Art (LACMA) and look at Japanese artworks, especially from the Jomon to Heian period. There were no event focusing on Japanese Art on LACMA, so I opted to join a Sunday tour of the Japanese art collection instead. Knowing at once that it would only last for 50 minutes, I wondered at first how the guide would condense the lecture of thousands of years of Japanese history and Japanese art, especially that it entails a lot of explaining and translating to do. But the explanations as we went along the way were brief and concise and focused on the artworks, but were enough for us to take note of. What I intended to focus on were paintings from the Jomon to Heian period of Japanese Art, but instead I took note of different forms of Japanese artworks which I found interesting. There were several pieces that caught my attention, but those that I focused on were a ceramic vessel from the middle Jomon period, Jizo Bosatsu, which is carved wood sculpture from the late Heian period, and Seated Warrior, a sculpture from the Kofun period. Japanese art on the Jomon period are mostly earthenware vessels, mostly deep pots made of clay. Potteries made from the Jomon period are characterized by rope markings, incised lines and applied coils of clay (Kleiner 91). These vessels, however psychedelically figured, have a variety of uses. They serve different purposes, from storage to burial (Kleiner 91). The vessels on the Japanese Art Tour on the LACMA mostly have textured bases, the incised rope markings very apparent, and have castellated rims. Japanese art on the Kofun period is completely different. According to the Minneapolis Institute of Arts Website, the art on this period is characterized by tombs furnished haniwa, or cylinders which are used as adornment for tombs on the era. The forms of the haniwa later evolved to simple geometric forms of houses, animals, birds, and other figures. The sculpture on the LACMA, however, resembles a Seated Warior form, hence, its title. The Heian period is characterized with artworks representing or illustrating Esoteric Buddhism (Kleiner, 2010). Most of the artworks are Buddhist deities sculptures carved from wood, to which people worship. The sculpture of deities were characterized by a wardrobe of a monks, and all of them stood on top of a lotus, which symbolizes rebirth, according to the tour guide. I have expected Japanese art to be intricate, except maybe those from the Jomon period. But it turned out that even from the Neolithic period, the Japanese already had a sense of aesthetics that their vessels are adorned with rope markings. For me, the abstract form of Jomon period art is its strength. The Kofun period art was indeed very interesting for me because the artworks were used to decorate tombs, and the decorations symbolizes the person in that tomb. Meanwhile, as expected, Heian art is deeply rooted on Buddhism, and has Chinese influences. At the end of the day, I realized that the evolution of Japanese art relied on what happened in Japan at the time these artworks were constructed. The colorful events strongly influences the frame of mind of the artists. History is what shapes art.

Essay --

The Connection Between Malaria and Deforestation Deforestation is the clearing of forests where the land is then converted for other uses. Deforestation happens globally on a massive scale as humans expand and cultivate the land. Examples of deforestation include the clearing of forests for cattle farming, mining and of course logging operations as well as a multitude of other uses. In the Amazon deforestation has been a problem for hundreds of years, ever since the Europeans ventured to the new world the Amazon has suffered from human settlement and the development of land. Because of these changes to the rainforest the ecosystem has been changed indefinitely. Malaria is an infectious disease born from mosquitoes that is caused by parasitic protozoa that reside inside the mosquito. In most cases the disease is transmitted through getting bitten by an infected female anopheles mosquito. the protozoa is transferred to the victim from the mosquitoes saliva into their circulatory system. Malaria symptoms usually include headaches as well as fever. In dire cases this can progress into a coma or can be fatal (CDC 2014). Malaria is typically found in warmer regions of the world mostly tropical and sub tropical countries. The reason for this is the Anopheles mosquito thrives in higher temperatures. Malaria parasites grow and develop inside the mosquito and needs warmth to complete its growth before they are mature enough to be transmitted to humans.. Some examples of areas that malaria is present include South America, Asia and Sub-Saharan Africa (CDC 2014). I believe that deforestations leads to an increase in the occurrence of malaria because of the increased survivability of the Anopheles darlingi mosquito in disturbed areas... ... improved due to land cultivation, all leading to an increase in malaria cases because of the upsurge of the Anopheles darlingi population. References †¢ Vittor, Amy Yomiko, et al. "The effect of deforestation on the human-biting rate of Anopheles darlingi, the primary vector of falciparum malaria in the Peruvian Amazon." The American Journal of Tropical Medicine and Hygiene 74.1 (2006): 3-11. †¢ Yasuoka, Junko, and Richard Levins. "Impact of deforestation and agricultural development on anopheline ecology and malaria epidemiology." American Journal of Tropical Medicine and Hygiene 76.3 (2007): 450. †¢ Olson, Sarah H., et al. "Deforestation and malaria in Mancio Lima county, Brazil." Emerging infectious diseases 16.7 (2010): 1108. †¢ "Malaria." Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 05 Feb. 2014. Web. 11 Feb. 2014.

Deception Point Page 107

Rachel fell onto her back against the cockpit's rear wall. Half submerged in sloshing water, she stared straight up at the leaking dome, hovering over her like a giant skylight. Outside was only night†¦ and thousands of tons of ocean pressing down. Rachel willed herself to get up, but her body felt dead and heavy. Again her mind reeled backward in time to the icy grip of a frozen river. â€Å"Fight, Rachel!† her mother was shouting, reaching down to pull her out of the water. â€Å"Grab on!† Rachel closed her eyes. I'm sinking. Her skates felt like lead weights, dragging her down. She could see her mother lying spread-eagle on the ice to disperse her own weight, reaching out. â€Å"Kick, Rachel! Kick with your feet!† Rachel kicked as best as she could. Her body rose slightly in the icy hole. A spark of hope. Her mother grabbed on. â€Å"Yes!† her mother shouted. â€Å"Help me lift you! Kick with your feet!† With her mother pulling from above, Rachel used the last of her energy to kick with her skates. It was just enough, and her mother dragged Rachel up to safety. She dragged the soaking Rachel all the way to the snowy bank before collapsing in tears. Now, inside the growing humidity and heat of the sub, Rachel opened her eyes to the blackness around her. She heard her mother whispering from the grave, her voice clear even here in the sinking Triton. Kick with your feet. Rachel looked up at the dome overhead. Mustering the last of her courage, Rachel clambered up onto the cockpit chair, which was oriented almost horizontally now, like a dental chair. Lying on her back, Rachel bent her knees, pulled her legs back as far as she could, aimed her feet upward, and exploded forward. With a wild scream of desperation and force, she drove her feet into the center of the acrylic dome. Spikes of pain shot into her shins, sending her brain reeling. Her ears thundered suddenly, and she felt the pressure equalize with a violent rush. The seal on the left side of the dome gave way, and the huge lens partially dislodged, swinging open like a barn door. A torrent of water crashed into the sub and drove Rachel back into her chair. The ocean thundered in around her, swirling up under her back, lifting her now off the chair, tossing her upside down like a sock in a washing machine. Rachel groped blindly for something to hold on to, but she was spinning wildly. As the cockpit filled, she could feel the sub begin a rapid free fall for the bottom. Her body rammed upward in the cockpit, and she felt herself pinned. A rush of bubbles erupted around her, twisting her, dragging her to the left and upward. A flap of hard acrylic smashed into her hip. All at once she was free. Twisting and tumbling into the endless warmth and watery blackness, Rachel felt her lungs already aching for air. Get to the surface! She looked for light but saw nothing. Her world looked the same in all directions. Blackness. No gravity. No sense of up or down. In that terrifying instant, Rachel realized she had no idea which way to swim. Thousands of feet beneath her, the sinking Kiowa chopper crumpled beneath the relentlessly increasing pressure. The fifteen high-explosive, antitank AGM-114 Hellfire missiles still aboard strained against the compression, their copper liner cones and spring-detonation heads inching perilously inward. A hundred feet above the ocean floor, the powerful shaft of the megaplume grabbed the remains of the chopper and sucked it downward, hurling it against the red-hot crust of the magma dome. Like a box of matches igniting in series, the Hellfire missiles exploded, tearing a gaping hole through the top of the magma dome. Having surfaced for air, and then dove again in desperation, Michael Tolland was suspended fifteen feet underwater scanning the blackness when the Hellfire missiles exploded. The white flash billowed upward, illuminating an astonishing image-a freeze-frame he would remember forever. Rachel Sexton hung ten feet below him like a tangled marionette in the water. Beneath her, the Triton sub fell away fast, its dome hanging loose. The sharks in the area scattered for the open sea, clearly sensing the danger this area was about to unleash. Tolland's exhilaration at seeing Rachel out of the sub was instantly vanquished by the realization of what was about to follow. Memorizing her position as the light disappeared, Tolland dove hard, clawing his way toward her. Thousands of feet down, the shattered crust of the magma dome exploded apart, and the underwater volcano erupted, spewing twelve-hundred-degree-Celsius magma up into the sea. The scorching lava vaporized all the water it touched, sending a massive pillar of steam rocketing toward the surface up the central axis of the megaplume. Driven by the same kinematic properties of fluid dynamics that powered tornadoes, the steam's vertical transfer of energy was counterbalanced by an anticyclonic vorticity spiral that circled the shaft, carrying energy in the opposite direction. Spiraling around this column of rising gas, the ocean currents started intensifying, twisting downward. The fleeing steam created an enormous vacuum that sucked millions of gallons of seawater downward into contact with the magma. As the new water hit bottom, it too turned into steam and needed a way to escape, joining the growing column of exhaust steam and shooting upward, pulling more water in beneath it. As more water rushed in to take its place, the vortex intensified. The hydrothermal plume elongated, and the towering whirlpool grew stronger with every passing second, its upper rim moving steadily toward the surface. An oceanic black hole had just been born. Rachel felt like a child in a womb. Hot, wet darkness all engulfing her. Her thoughts were muddled in the inky warmth. Breathe. She fought the reflex. The flash of light she had seen could only have come from the surface, and yet it seemed so far away. An illusion. Get to the surface. Weakly, Rachel began swimming in the direction where she had seen the light. She saw more light now†¦ an eerie red glow in the distance. Daylight? She swam harder. A hand caught her by the ankle. Rachel half-screamed underwater, almost exhaling the last of her air. The hand pulled her backward, twisting her, pointing her back in the opposite direction. Rachel felt a familiar hand grasp hers. Michael Tolland was there, pulling her along with him the other way. Rachel's mind said he was taking her down. Her heart said he knew what he was doing. Kick with your feet, her mother's voice whispered. Rachel kicked as hard as she could. 130 Even as Tolland and Rachel broke the surface, he knew it was over. The magma dome erupted. As soon as the top of the vortex reached the surface, the giant underwater tornado would begin pulling everything down. Strangely, the world above the surface was not the quiet dawn he had left only moments ago. The noise was deafening. Wind slashed at him as if some kind of storm had hit while he was underwater. Tolland felt delirious from lack of oxygen. He tried to support Rachel in the water, but she was being pulled from his arms. The current! Tolland tried to hold on, but the invisible force pulled harder, threatening to tear her from him. Suddenly, his grip slipped, and Rachel's body slid through his arms-but upward. Bewildered, Tolland watched Rachel's body rise out of the water. Overhead, the Coast Guard Osprey tilt-rotor airplane hovered and winched Rachel in. Twenty minutes ago, the Coast Guard had gotten a report of an explosion out at sea. Having lost track of the Dolphin helicopter that was supposed to be in the area, they feared an accident. They typed the chopper's last known coordinates into their navigation system and hoped for the best. About a half mile from the illuminated Goya, they saw a field of burning wreckage drifting on the current. It looked like a speedboat. Nearby, a man was in the water, waving his arms wildly. They winched him in. He was stark naked-all except for one leg, which was covered with duct tape.