TOEFL background -11

 Petrified Forest a little background knowledge exists in the United States
Petrified Forest Painted Desert in Arizona, is widely distributed in the petrified wood and fossil tree gathering place. Silica from the ash dissolved in water and into the trees, into crystals, petrified wood will be formed at this time. People now see the bright colors of petrified wood is added from other minerals are formed.
some petrified wood looks as if the ax had been cut off for use as firewood , but they may be formed by the earthquake rupture. agate bridge (Agate is a semi-precious stones) that span 12 meters wide in a single stream at the top of petrified wood. It does not support the span, but both ends of the buried sandstone.
precious fossil collectors in the past have caused great damage to forests, petrified wood is now protected by law, which no longer take away a piece of stone.
Native Americans have an explanation Petrified Forest The story of how. a goddess for the set of wood for cooking, but not burn the wood is wet. goddess was very angry, they impose the evil spell of some wood, these were turned to stone, can not be used by any person .

Ballet Ballet Ballet
acquaintance (Ballet) word from the Italian Ballare, meaning dance, specifically refers to in its development process, due to often to describe the performances in this dance the story, and gradually formed a special performance in the form of .1772, Charles b Diderot (Charles Didelot) in the French Encyclopedia, said: Department of interpretation of the ballet dance action with the special requirements hh theatrical feast for the eyes hh and sets, to the performance of a poetic, or a series of concepts, or a story of the plot. not unfamiliar, especially in recent years, the ballet has been an increasing number of concept note, a surge of crowded, all Chinese and foreign performing groups for the majority of the audience presented a wonderful performance after another platform, really, > ballet conceived in Italy, was born in the late seventeenth century French court of Louis XIV, the French daily perfect in the eighteenth century to the late nineteenth century, in Russia access to the most prosperous period. ballet a long history in the past forty years the development process, a great impact on the world, spread wide, has become the world are trying to develop an art form out.
ballet history can be traced back since the beginning of the earliest European Renaissance Man Island peak During the Italian court, and the younger brother of Bergen in southern France where the court. Every marriage celebrations, meeting with foreign heads of state, or other big celebration, that is, to show that I wish the dance performances or performances. ballet history of the first relatively complete ballet mm regarded as the oldest ballet music.
ballet to Louis XIV Dynasty (1643m1715) Zhen heyday era, Louis XIV himself was a extraordinary dancer, Juxi did ballet performances .1661, the Louis XIV created the the first dance school history mm French Royal Academy of Dance, taught dancing. This school is now the Paris Opera House. and used since the hands of the five locations, and some beautiful ballet dancing was here in 1700 are fixed . dancing master at the Royal Beauchamp (Beauchamp) and musicians Beverly (Cambefort) and Lvli (Lully) strongly advocated, the French ballet music in the culture and the importance of greatly increased. So many new ballet into court dance of the source; such as: Jia Wote Dance (Gavotte), Bass Pierre Dance (Passepied), Bray Dance (Boree), Rodrigo Eastern dance (Rigaudon) and so on. In the dance, the most important must be the Menuet (Minuet), Lv Li in 1653, the French court ballet began to participate in activities to achieve orgasm. he was working with Moliere (Moliere) together to produce the so-called hybrid theater and ballet ballet comedy (Comedie Ballet) .1760 published in Mo (Rameau) did the same. especially the works of Rameau, for inclusion of Mexico, China and other foreign health and mood of the more funny. This, of course, and his personality and background. Britain has created a special kind of ballet , name, called concept in the 20th century, more or less still its aftermath, and sometimes debated.
from the beginning of 1789, there was an representative. By the 19th century, has appeared in Paris, 1870) as the representative of the masterpieces of, and then in Russia into the Lake Ballet Ballet the former Soviet Union's Kirov Ballet and Bolshoi Ballet, in New York City Ballet and American Ballet Theatre, the British Royal Ballet, Paris Opera Ballet and the Royal Danish Ballet. Contemporary Ballet presents unprecedented popularity and prosperity, representative figures and groups to b Ji Lian Czech Jiri (1947m) and his Netherlands Dance Theatre and the American William b Fawcett (1949m) and his Ballet Frankfurt, Germany.
toe Art
the actual needs from the movement point of view, the invention of toe shoes to support the weight of the dancers body friction with the ground to improve the speed of rotation, resulting in the effect of maneuvering, the illusion of vulgarity, and then better for Love immortal ballet fantasy themes such services.
body from the ballet aesthetic, is is a toe dance toe shoes and the technology used to dance ballet and other types distinguished. Of course, this difference is mainly in terms of only the female dancers. and folk dance and modern dance contrast, ballet as a noble The Western classical dance, and daily life is the farthest distance. but in life and art of this line from the standard, it is the most artistic of a dance.
from the unity in terms of content and form, language as a kind of ballet moves furthest away from the life of dance forms, the most elusive for the performance of the kind of immortal love of the content, thus completing the form and content of the high degree of unity.
aesthetic from the ballet Ideally, the use of toe shoes to the original slender dancer body will be further stretched the line to extend this particular beauty, and enhance the impact of space to expand the amount of space occupied, and often far beyond the human body the proportion of anatomical structure, increase the daily life of ballet and distance, vividly reflect the hour to reach theaters in order to be able to daily chores and worries were all left outside the gate in the theater, and then settle down, threw himself into a very special theatrical aesthetic field. modern appreciation of ideas that is how the story in the end ; write salute to the phenomenon of the spectators?
process in the ballet, the not even think, just walking into the theater, from the and the immediate response and kinesthetic understanding.
20 standard ballet technique: 1, rotation: the level of quantity and quality of ballet technique for judging the level of one of the core standards, the so-called quality, mainly refers to the rotation , the standard dance is out of shape, spatial location is in compliance with requirements, and stop the stability of rotation as ever, whether naturally when completed at the end of a fixed dance .2, speed: This is a measure of the level of ballet technique as another hard scale. faster, the greater the difficulty, in some spins and jumps, the speed is essential, and the completion of these actions together can make it easier. Of course, the pace is just a technology standard, non-art standards. there comes to the the third level of identification technology standards. in dynamic changes of direction, require the efforts to change properly, and experienced dancers all know, according to the schedule around in circles than in a circular motion in a straight line scheduling more difficult, while the woman kept in a fixed-point turn to complete the 32 weeks whiplash, or men are also done on a fixed point of dozens of turn two next to the legs, the dancers are often a measure of the touchstone of technical level .4, to see a little point: the so-called ; point to see a little especially the eyes, left behind, until the entire head and body separation between the maximum limit, that is, when the second rotating body to the moment before, the head and eyes to follow the entire body abruptly momentum rejection of the past, and immediately faster than the speed of the body, in time for the whole body before completing a full circle, to find that the original point of view, and then tightly pegged to the link, this is the best way to avoid dizziness dancers. This practices in fact, mine is to use the army is less than the speed of their ears, resulting in a static illusion to take advantage of the shortest time to complete the visual changes in this direction to reduce the balance organs of the oscillation and changes, to avoid the resulting .5 dizziness, changes in arm or legs: changes in the spin or jump in the arms or legs, is the dancer's body balance and coordination is another major challenge .6, silent and elegant floor: this should be the judge dancers of the level of .7 and a standard, high jump: This is of course to increase dance appreciation in the warm sentiments. In comparison, far less to create absolute height to maintain a high degree in an instant, and even pause in the air, the illusion that difficult. In the eyes of experts to create this illusion is the art of one of the most brilliant dancers. It was at this moment where the dancer as a human, or human characteristics of the dancers to get the biggest forward, and nature gravity is the greatest contempt by .8, stretch knee: This is absolutely essential for ballet technique specification .9, stretch toes: This is the technical perfection of ballet and the basic requirements of .10, the high leg lift: from Reception point of view, the dancers are facing the audience, to the high leg lift on both sides of the effect of .11 more, the stability of the supporting leg: complete this action idealized standards, in addition to outside knee and foot need Bengzhi , also called as virtual certainty as the supporting leg, motionless .12, the line: roughly divided into two categories, one is physical line dancer, is the stage of scheduling a class lines .13, fluency: According to the Chinese and foreign traditional dance way, choreographer and the audience asked the dancers are accustomed lines and stage movements smooth operation if the water lines .14, Pas de Deux: include lift, rotate and balance the three main types of support actions. an outstanding addition to the tacit understanding between partners the performance of routine actions in the pas de deux to the extent of by heart, but also the performance of mutual trust in the absolute top of .15, a large group dance: if they had to go, hands and feet must be in place, action must be consistent, breathing must be unified, sentence must be smooth dance, dance must be coordinated. large-scale dance, every dancer's individuality should be the maximum inhibition, in order to maintain the harmonization of the whole picture .16, clean and accurate: whether groups or individuals, the action should be clean dancers and accurate .17, dancers dancing, should show a full and elegant self-confidence, especially in the simple and difficult moves to complete prior to and should not show any anxiety to, but should give Rulvpingdi the relaxed and comfortable feeling and the sense of the overall coherent and comfort .18, pleasure: the dancers as theater artists, their duty should be to provide pleasure to the audience, but to provide pleasure, the dancers dance course I must be as find their own pleasure .19, a small trick: When the ballet dancers on stage, not in strict accordance with the technical specifications and accurately complete a variety of action, will not help to make some small compensation or adjustment, jargon is called fraud. deceive the audience, like magic magic is that it's temporal relationship between the intensity, the dancers should be resolved in the rehearsal.
indirectly determine the quality level of the four perspective: 1, ballet performances are engaging, the audience can not be lazy or lying on the ground or by the chair, but only the first part of sitting in a chair, straight Bogeng, eyes wide open, staring look; 2, ballet performances arbitrary state whether they have met, or at least left to the audience the impression of calm; 3, ballet dancers in performance is achieved forget the details, just follow the logic of its own forward movement of the realm; 4, and ballet in the show, if just left to run with the body in space, to forget everything between secular Impression of trouble.
some understanding of American culture, history, and so the background music tourism sites


ancient times to the writer describes the United States introduced



jazz Introduction

all places of interest in American history

American college life
Neoclassical and Romantic Literature
Earth rotation time becomes shorter
We have been talking about some of the effects that the human beings had on the earth. One you may not be aware of is that we actually begin to change the length of the day. In the other way to say, one day is the amount of time the earth needs to spin completely around an axis, the imaginary line around the center of the earth, from the north to the south. And of course there are a lot of physical causes that can affect the speed of the earthrs rotation, but there was only one that is direct result of the human activity. Since 1950, human beings have built about ten thousand artificial reservoirs all over the world. These reservoirs have redistributed tremendous amount of the earth water. When they are used to be in the area near the equator, the imaginary line surround the middle of the earth, itrs now the reservoirs in the areas of different latitudes. The latitude matters because, well, thinking the earth and axis, the equator contains the areas on the earth that are the farthest away from axis. So water has been redistributed from the equator regions, then wherever the water is, to itrs close to the earth axis. Itrs like when ice skaters perform spins when those skaters put their arms enclose to their bodies, they spin faster. So the earth is spinning faster because the reservoirs have redistributed the water close to its axis. And because the earth was spinning faster, since 1950 the length of day has decreased by about 8 millionth of second. I know that doesnrt sound like much but significant in that this is the first time that human beings ever had measurable affect on the earthrs motion.
tidal power
who lived by the sea on the people know, when the sea water back into the sea rising and falling. seawater is that the people of this natural fluctuation phenomena often said of the tide. Tidal Moon tidal force from the sea could rise 0.246 m, the joint action of the two, the maximum tidal range of tides is 8.9 meters; North America, Bay of Fundy the largest tidal range in Hong Kong actually Moncton up to 19 meters. It is calculated that tidal energy reserves of the world's oceans about 27 million kilowatts, if all converted into electricity, generating an annual volume of about 1.2 trillion degrees. tidal power, strictly speaking should be called , tidal power is only a kind of marine energy generation, but it is the development of ocean energy utilization of the earliest and largest of a more mature technology.
modern marine energy development mainly refers to the use of marine energy generation. use of marine power generation in many ways, including wave power generation, tidal power, tidal power, sea water temperature difference power generation and power generation, water containing salt, while at home and abroad have been developed mainly by ocean tidal power to generate electricity. As the cost of tidal power development higher and technical reasons, so the slow development.
principles of tidal power and hydroelectric power are similar it is to use the tide rises, the water level down by poor production has potential to generate electricity, that is, the water rose, the ebb tide energy into mechanical energy, then mechanical energy into electrical energy (power generation) process. Specifically, tidal power is a tidal estuary bay or build a stone check dams, will be separated by a bay or estuary and ocean composition reservoir, and then in dam or the dam hydro-generating unit installed room, and then using tidal fluctuations of sea level rise and fall time, so that sea water through the turbine generator set of rotational power.
the flow of the tide and river flow different, it is constantly changing direction, so the emergence of tidal power to make different types, such as: �� one way in one database type, can only generate electricity at low tide. �� way one database type: the rose, can generate electricity at low tide. �� two-way type of library : can continuously generate electricity, but economically viable, and no practical application. 4 practical application of tidal power to be most important in Germany in 1912 built a small Husum tidal power plant, which began to become the ideal tidal power reality. the world's first economic value, but also the world's largest tidal power station is the west coast of France in 1966, Lancelot tidal power plant construction, it makes tidal power plant into the practical stage, the installed capacity of 24 kW, with an annual generating capacity of 544 million degrees .1968 Barents Sea in the former Soviet Union built Jisi Luo tidal power plant, the total installed capacity of 800 kilowatts, the annual generation capacity of 230 million degrees. China's coastal areas have been completed and nine small tidal power plant, built in 1980, River Tidal Power Plant is China's first tidal power station is a larger world of tidal power station, the attendant capacity of 3,200 kilowatts, the annual generation capacity of 1,070 million degrees.
water Power
gigantic natural hot library is both a vast ocean
gigantic depths of the sea water temperature, a difference of up to above 20 ��. People usually for each additional 100 meters of water depth difference between the temperature of seawater called Maximum temperature lapse rate; depth of more than 200 meters or more, the temperature decrease rate was significantly reduced; depth of 1,000 meters or more, the temperature lapse rate has become quite a small.
ocean water temperature differences between upper and lower bears certain energy, the scientists call 28 �� to add warm water (which is equivalent to the sea surface temperature); connected to the other side of the flask into the ice in B, and maintain the water temperature 0 �� (to represent the deep-sea water temperature.) A flask with a vacuum pump to the air out (low pressure pumped 0.038 per square centimeter). Since the boiling point of liquid is added to the liquid surface with the decrease of pressure reduction, so in this low pressure, sufficient to make the flask of water boiling up 28 ��. If can make the vacuum flask to further improve, that is, the pressure inside the flask becomes lower, then the flask of warm water will evaporate rapidly boiling in advance. In this way, compared to flask B ice within 0 �� to water vapor pressure difference produced mainly by the pressure difference. So, A flask of water vapor within the evaporator through a nozzle, turbine generator sets for power generation drive.
Claude tests are successful, in 1929 in Cuba devoted to the construction of a water temperature difference power generation apparatus. He used copper pipe with a diameter of 2 meters, at a distance of 2000 meters at the coast, 650 meters from the sea to draw cold water. When the temperature of sea water temperature is 27.5 �� and The temperature of cold water 13 ��, its power output is 22 kilowatts. However, he extracted with cold water when the pump power consumption is 80 kilowatts. Is this not Germany's power generation potential of this experimental device did not get full play, to calculate the power output by up to 220 kilowatts. but in any case, Claude experiments show that: the use of sea water temperature for power generation is technically feasible .
water temperature is now a new generation device, is the first to introduce solar heating pool water, the water heated to 45 ~ 60 �� (some up to 90 ��), then the introduction of warm water to maintain a vacuum a space to make it evaporate, by means of steam to drive turbine for power generation.
is common practice, however, the use of ammonia as the working substance, the surface with ammonia to absorb heat and evaporate water into the ammonia vapor to promote Turbine to generate electricity. finished work was taken after the ammonia condenser (cold seawater from the deep condensation), and then back through the pump will pump the liquid ammonia into the evaporator, while the ammonia re-use of surface water evaporation, continue to generate electricity.
use of sea water temperature difference to generate electricity, but also can be a byproduct mm fresh water, so that the temperature difference between sea water desalination power generation but also the function of both. a generation capacity of 10 million kilowatts of power plant water temperature, each days out of 378 cubic meters of fresh water fractionation, to address the needs of industrial water and drinking, on the other hand, since taking power in the deep cold nutrient-rich salt sea water, so water temperature around the power station, it is plankton and the ideal place to fish habitat, which will improve inshore fish catches.
for power generation using sea water temperature, water temperature is usually chosen over the sea at 20 ��. Cuba, Brazil, Angola, Indonesia and China low-latitude southern coastal waters of the sea water temperature is ideal for power generation. According to the experts estimate that only 20 north latitude. to latitude 20. between the sea, the sea temperature difference is enough generating capacity to 26 million kilowatts. the world's oceans water temperature difference energy reserves can power about 60 billion kilowatts. in our waters, the availability of water temperature difference energy power generation of about 120 million kilowatts.

amazing spider silk for military purposes
biological steel refers to the goat steel, also refers to milk steel. goat and milk, and steel have been irrelevant, but scientists are skillfully combined to shift the.
1997 year, the United States biologist Anne b Moore found that, in the southern United States have called different types of silk into a spider web, the first wire in the pull-off before the 27% can be extended, and its strength goes to other spider silk 2 times; second wire in the pull-off before the little extension, but have a very High anti-breaking strength, by this spider silk cloth, than the manufacture of the fiber used in bulletproof vests strength is also much higher. if there is a way as spider silk can be produced as high-strength fibers nice.
scientists think so the milk protein genes contain scientific experiments. let the goat and the egg ...