亓亓小屋
With human beings on Earth since then, we continue to evolve at the same time has been hurt those lovely animals. They did not at fault, they are only in accordance with the laws of nature live in peace. But since the existence of mankind , their homes become increasingly small. Some animals have even become extinct. In the extinction of animal, the thylacine is the worst. Thylacine in a long time ago to live in the vast prairie, they have been very happy, carefree. Since the arrival of human beings have changed their lives. Due to the large number of human enclosure, livestock grass makes less and less change to many herbivores to move to other grasslands. This herbivorous animals to eat the wolf bag, there is no food. They steal human animals. Farmers would hate the wolf from the bag, see a killing one, on this last one wild thylacine was also killed. When people should be aware of extinct thylacine, the protection of the park began last a thylacine, it thylacine only 48 days before the final days. And 48 days later, the Forever thylacine disappeared from the Earth, the Forever! Of course, not all animals are extinct human killing, some changes in the environment are not suited extinction. However, the extinction of some animals, human beings have an unshirkable responsibility. Since ancient times human beings have been cruel to those animals alone, human deprivation of their right to live. Now seems to have been aware of the extinction of an animal hazards. In order to make money, what people are willing to do so, they sell fur animals, shopping malls, the meat of animals sold to restaurants. But we can not shirk all responsibility to the heads of traders, consumers also have the responsibility, if there is no consumer demand then the traders will not take the risk. Human beings are still eating wild animals. For example: the snake. If the extinction of the snakes, rats would wantonly breeding, then how do we ... ... So each has its biological significance of the existence, they are in the natural law of survival. If a broken food chain, then another will wantonly breeding animals, and even a threat to humanity, we bear in mind the protection of animals. The protection of animals is to protect human beings themselves!参考译文：自从地球上有了人类以后，我们在不断地发展进化的同时也在不断的伤害着那些可爱的动物们.他们没有过错,他们只是根据自然界的法则和平的生活着.可是自从有了人类的存在,他们的家园变的越来越小.有些动物甚至已经灭绝了. 在灭绝的动物里，袋狼算是最惨的了。在很久以前袋狼生活在广阔的大草原上，它们过的很快活，无忧无虑。自从人类的到来改变了它们的生活。由于人类的大量圈地，饲养牲畜使得绿草变地越来越少，许多食草动物迁徙到别的草原上。这样以草食性动物为食的袋狼就没有了食物。它们便去偷人类饲养的动物。农场主便痛恨起了袋狼，见一个杀一个，就这样最后一只野生袋狼也被杀死了。当人们意识到袋狼就要灭绝时，才开始保护公园里的最后一只袋狼，这只袋狼才过了最后48天的好日子。而48天后，袋狼永远的从地球上消失了，永远的！ 当然不是所有灭绝的动物都是人类杀死,有的是不适应环境的变化而灭绝的.但是某些动物的灭绝，人类有着不可推卸的责任。人类自古以来就一直残忍地对待着那些动物们,人类剥夺了它们生活的权利. 现在人们似乎还没有意识到一种动物的灭绝的危害。为了赚钱人什么都愿意做，他们把动物的皮毛卖到商场，把动物的肉卖到餐馆。但是我们不能把一切责任都推卸到商贩的头上，消费者也有责任，如果没有消费者的需求那么商贩也不会铤而走险。人类还在吃着野生动物。比如：蛇。如果蛇灭绝了，老鼠会大肆繁殖，到那时候我们该怎么办…… 因此每一种生物都有它存在的意义，它们都在以自然的法则生存。如果生物链的一头断了，那么另一种动物就会大肆繁殖，甚至威胁到人类，大家记住保护动物。保护动物就是保护人类自己！ 选我吧...............
suki子雅
Small and shy—or big and fierce? Bright as a jewel—or hardly visible? Four legs? Two legs? No legs at all? When you're talking about lizards and snakes-the squamates-the answer is usually . . . Yes! This ancient group, whose scientific name is Latin for "scaled," is more diverse than mammals, as old as dinosaurs. And they're almost everywhere: harsh desert to lush rainforest, high in the treetops, beneath the ground. Whatever the environment, one of the 8,000 squamate species on Earth calls it home. We share the planet, but we often overlook these quiet neighbors. So welcome to the world of squamates, and get ready to be surprised!
Nicole800328
Science is both a body of knowledge and a process. In school, science may sometimes seem like a collection of isolated and static facts listed in a textbook, but that's only a small part of the story. Just as importantly, science is also a process of discovery that allows us to link isolated facts into coherent and comprehensive understandings of the natural world. Science is exciting. Science is a way of discovering what's in the universe and how those things work today, how they worked in the past, and how they are likely to work in the future. Scientists are motivated by the thrill of seeing or figuring out something that no one has before
我们的季节
Phonograph - History
The first great invention developed by Edison in Menlo Park was the tin foil phonograph. While working to improve the efficiency of a telegraph transmitter, he noted that the tape of the machine gave off a noise resembling spoken words when played at a high speed. This caused him to wonder if he could record a telephone message. He began experimenting with the diaphragm of a telephone receiver by attaching a needle to it. He reasoned that the needle could prick paper tape to record a message. His experiments led him to try a stylus on a tinfoil cylinder, which, to his great surprise, played back the short message he recorded, "Mary had a little lamb."
The word phonograph was the trade name for Edison's device, which played cylinders rather than discs. The machine had two needles: one for recording and one for playback. When you spoke into the mouthpiece, the sound vibrations of your voice would be indented onto the cylinder by the recording needle. This cylinder phonograph was the first machine that could record and reproduce sound created a sensation and brought Edison international fame.
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Electricity and Lightbulb - History
Thomas Edison's greatest challenge was the development of a practical incandescent, electric light. Contrary to popular belief, he didn't "invent" the lightbulb, but rather he improved upon a 50-year-old idea. In 1879, using lower current electricity, a small carbonized filament, and an improved vacuum inside the globe, he was able to produce a reliable, long-lasting source of light. The idea of electric lighting was not new, and a number of people had worked on, and even developed forms of electric lighting. But up to that time, nothing had been developed that was remotely practical for home use. Edison's eventual achievement was inventing not just an incandescent electric light, but also an electric lighting system that contained all the elements necessary to make the incandescent light practical, safe, and economical. After one and a half years of work, success was achieved when an incandescent lamp with a filament of carbonized sewing thread burned for thirteen and a half hours.
There are a couple of other interesting things about the invention of the light bulb: While most of the attention was on the discovery of the right kind of filament that would work, Edison actually had to invent a total of seven system elements that were critical to the practical application of electric lights as an alternative to the gas lights that were prevalent in that day.
These were the development of:
1.the parallel circuit,
2.a durable light bulb,
3.an improved dynamo,
4.the underground conductor network,
5.the devices for maintaining constant voltage,
6.safety fuses and insulating materials, and
7.light sockets with on-off switches.
Before Edison could make his millions, every one of these elements had to be invented and then, through careful trial and error, developed into practical, reproducible components. The first public demonstration of the Thomas Edison's incandescent lighting system was in December 1879, when the Menlo Park laboratory complex was electrically lighted. Edison spent the next several years creating the electric industry.
The modern electric utility industry began in the 1880s. It evolved from gas and electric carbon-arc commercial and street lighting systems. On September 4, 1882, the first commercial power station, located on Pearl Street in lower Manhattan, went into operation providing light and electricity power to customers in a one square mile area; the electric age had begun. Thomas Edison's Pearl Street electricity generating station introduced four key elements of a modern electric utility system. It featured reliable central generation, efficient distribution, a successful end use (in 1882, the light bulb), and a competitive price. A model of efficiency for its time, Pearl Street used one-third the fuel of its predecessors, burning about 10 pounds of coal per kilowatt hour, a "heat rate" equivalent of about 138,000 Btu per kilowatt hour. Initially the Pearl Street utility served 59 customers for about 24 cents per kilowatt hour. In the late 1880s, power demand for electric motors brought the industry from mainly nighttime lighting to 24-hour service and dramatically raised electricity demand for transportation and industry needs. By the end of the 1880s, small central stations dotted many U.S. cities; each was limited to a few blocks area because of transmission inefficiencies of direct current (dc).
The success of his electric light brought Thomas Edison to new heights of fame and wealth, as electricity spread around the world. His various electric companies continued to grow until in 1889 they were brought together to form Edison General Electric. Despite the use of Edison in the company title however, he never controlled this company. The tremendous amount of capital needed to develop the incandescent lighting industry had necessitated the involvement of investment bankers such as J.P. Morgan. When Edison General Electric merged with its leading competitor Thompson-Houston in 1892, Edison was dropped from the name, and the company became simply General Electric.
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cynthiahql
Thoughts after reading The Wizard of Ozread some book called < bookworm >, it was written by L.Frank Baum, the famous United States writers. He wrote lots of wonderful novels .One of the most famous is the Wizard of Oz.This book stresses: a girl named Dorothy, was taken to another world tornado, she met a need for thinking of the Scarecrow. A need for Heart of the tin man and need the courage of lion.They defeated abhorrent Witch.Finally get the things they want.Dorothy returned to their homes.This fairy tale story of breathtaking twists and turns, praised the kindness, courage and the quality of fraternity and mutual help, ideal for the spirit of persistent struggle, is always worthy of our study.
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