Gunpowder 火药Handgun from the Yuan dynasty, circa 1300s.The prevailing academic consensus is that gunpowder was discovered in the 9th century by Chinese alchemists searching for an elixir of immortality. By the time the Song Dynasty treatise, Wujing Zongyao was written by Zeng Gongliang and Yang Weide in AD 1044, the various Chinese formulas for gunpowder held levels of nitrate in the range of 27% to 50%. By the end of the 12th century, Chinese formulas of gunpowder had a level of nitrate capable of bursting through cast iron metal containers, in the form of the earliest hollow, gunpowder-filled grenade bombs.In AD 1280, the bomb store of the large gunpowder arsenal at Weiyang accidentally caught fire, which produced such a massive explosion that a team of Chinese inspectors at the site a week later deduced that some 100 guards had been killed instantly, with wooden beams and pillars blown sky high and landing at a distance of over 10 li (~2 mi. or ~3.2 km) away from the explosion.By the time of Jiao Yu and his Huolongjing in the mid 14th century, the explosive potential of gunpowder was perfected, as the level of nitrate in gunpowder formulas had risen to a range of 12% to 91%, with at least 6 different formulas in use that are considered to have maximum explosive potential for gunpowder. By that time, the Chinese had discovered how to create explosive cannonballs by packing their hollow shells with this nitrate-enhanced gunpowder.。
The four great inventions Paper: paper is an important chemical processes, the invention of paper is Chinese in the spread of human culture and development make a valuable contribution, is China's chemical history of a major achievement. The paper also before, oracle bones, bamboo slips and silk silk is used for writing, the ancient recorded material. But due to the rapid development of the economy, culture, bones and bamboo can not meet the demand of development, thus contributing to the improvement of writing tools. At that time people began using small silk made of paper, as the ancient Chinese when paper by hemp thread and silk, and preparation method of rough paper, so the quality is not so good. But the hemp thread and silk has its own role, to use them as a raw material for paper-making, would be greatly restricted, and difficult to get rapid development, to meet the cultural life of the requirement to paper. In the new situation request, Cai Lun of Eastern Han Dynasty for the emergence of papermaking to bring new breakthrough in the Eastern Han Dynasty," views on" 2 records:" Cai Lun, talented, dedicated to cautious, every vacation, closed to the guest, aeration body field. Code for the sale, made with bark and spacious cloth, net to make paper. Xing Yuan first year playing, the emperor can, since is not used, the salty called Cai Hou paper". From above, Cai Lun is using bark, rags, net of papermaking. Although before Cai Lun also has a paper, but raw material itself is very limited, and Cai Lun on the new raw materials, to solve this problem. Because the rag, broken fishnet had already finished their task, a waste and used as a raw material for papermaking industry, which plays an important role. Printing: is the working people in ancient China through long-term practice and research before the invention of. About the year before and after 600 years of Sui Dynasty, people from the engraved seal inspired, in the history of mankind's earliest invention of woodblock printing. Woodblock printing is in a certain thickness of the smooth wood, paste copy neat manuscript, thin and almost transparent paper front and wood paste, the word became the body, strokes clear. Engraving workers graver in the suites have writing section is cut away, is a convex embossed font, and font recessed beneath the different steles. When printing, on a raised fonts with ink, and then the paper covering on top of it, gently wipe away the paper back, writing remain on the paper. By the Song Dynasty, woodblock printing career development to the heyday. Woodblock printing on the spread of culture play an important role, but also has obvious disadvantages. The first version, time-consuming material costs, second, a large number of books stored inconveniently, third, is not easy to correct mistakes. The Northern Song Dynasty civilian inventor Bi Sheng invented movable-type printing, woodblock printing these drawbacks improvement. Bi Sheng's Dynasty of an ordinary civilian intellectuals, the person who. He summed up the block printing of rich experience in practice, after repeated tests, the emperor Renzong of evolution years (AD 10411048 ) made the moveable, execute typesetting printing, completed the printing history of a major revolution, about 200 years later, this technology spread to other countries, the development of world civilization process to promote the role of. Gunpowder: is one of the four great inventions of china. Gunpowder, as the name suggests is the ( fire medicine ). Its origins and alchemy are closely related, Bachelor in ancient alchemy alchemy inadvertently material. It is a mixture of saltpeter, sulfur, carbon, and the top two in the Han Dynasty book into Chinese Materia Medica ( first classics of Shennong materia medica by ) have been listed as important medicinal herbs. Gunpowder itself is also come under the drug class, the Ming Dynasty Li Shizhen ( compendium of Materia Medica ) said, gunpowder can cure sore ringworm, insecticidal, provide moisture and plague. The invention of gunpowder is a long-term alchemy pharmaceutical practice results, has been one thousand years of history. The Tang Dynasty, gunpowder has been used for military. The Song Dynasty, the war continuously, promote the accelerated development of gunpowder weapons. The government of the Northern Song Dynasty established a powder mill, has made gunpowder arrow, artillery and other combustion properties mainly weapons and ( bang cannon ), ( lightning bombs ) and other explosive strong arms. The Southern Song Dynasty were created in 1259 to giant bamboo 。
Gunpowder, also known since the late 19th century as black powder, was the first chemical explosive and the only one known until the mid-1800s. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpeter)—with the sulfur and charcoal acting as fuels, while the saltpetre works as an oxidizer.Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as apyrotechnic composition in fireworks。
Gunpowder, also known since the late 19th century as black powder, was the first chemical explosive and the only one known until the mid-1800s.
It is a mixture of sulfur, charcoal, and potassium nitrate (saltpeter)—with the sulfur and charcoal acting as fuels, while the saltpetre works as an oxidizer.Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as apyrotechnic composition in fireworks.
， 是瑞典大化学家， 被誉为"炸药大王".他出生在瑞典首都斯德哥尔摩.他父亲热爱科学， 一心想用自己的智慧创造出世界上没有的东西.有一年， 诺贝尔家失了火， 弄得家中一贫如洗， 只得漂洋过海到俄国谋生.父亲开了一家日用五金商店， 还设了一个装满机械和各种化学药品的小实验室， 在经商之余从事科学实验. 小诺贝尔经常看到工人为了开凿铁路在荒山野岭手拿铁镐砸石头， 既费劲又费时.父亲发明了一种炸药， 不费劲地把大山劈开了.他对这种神奇的炸药着了迷， 喜欢陪父亲汔在实验室里.他记熟了各种化学物品的名称， 常向父亲提出各种不懂的问题， 父亲总是耐心地给他讲解， 还指导他做小实验. 诺贝尔17 岁的时候， 父亲决定让他去周游世界， 开开眼界.他兴奋地问父亲： "我这次旅行的任务是什么？"父亲严肃地说： "你只身离家， 远渡重洋， 是为了学习各国新的科学和技术.明白吗？"诺贝尔点点头. 诺贝尔遵照父亲的旨意， 先后到了德国、意大利和法国， 又去英国参加了世界博览会， 最后横渡大西洋， 到美国的机械工厂当了一名学徒工. 诺贝尔这次旅行整整用了两年.他除了尽情观赏了世界各地的奇异风光外， 还学习了许多新的科学技术和一些科学实验， 拜访了著名科学家、教授和学者， 大大地开阔了眼界， 增长了见识. 诺贝尔回到祖国， 继承父亲研制炸药的事业， 有一次在实验室里做实验， 突然炸药爆炸， 他差点儿被炸死， 实验室也炸毁了.但他不灰心， 又进行了上百次的实验， 终於成功了， 炸药的专利使他积聚了大量的财富， 他临终前留下遗嘱： 将全部财产捐献出来， 设立学术奖金， 鼓励全世界一切献身於科学事业的人。
Legend has it that before 1400, Nanchuan river when the smell of a man was killed by the mandrill, even Tang Taizong Li Shimin had long disturbed restless, then under the imperial national treatment. Born in Hunan Liuyang Nan Xiang Da Yao Li Tian took pains to develop fireworks, it is not only used to drive away evil spirits evil, protect the safe side, more Taizong flooding town evil spirit. Li Tian Jiujia meritorious, therefore has been called the "emperor Tang Taizong founder of firecrackers".
Folklore reflects Chinese people's beautiful and good wishes. But according to the history books and related literature books records, in Tang Dynasty has been the invention of fireworks, in the Northern Song Dynasty Xuanhe (1119 - 1125), using powder as raw material of our country real fireworks developed, has a frame into large-scale fireworks.
三篇收集的作文，望采纳1、In modern life we have many inventions.Thesemachines are very useful.They can make things better and faster than people.A washing machine can help us wash clothes.We have more time to do that we want to doduring this time.A printing machine prints a lot of books,newspapers and other things qiickly.Buses,bikes,cars,trains,planes and shipshelr us travel faster than before.The compter is wonderful machine.It is one of the most important inventions. Today it is used in many ways.It can store innformations and work out math problems millions of times faster than a person can.In a few years,the computer may touch the lives of everyone.Even people in faraway villages.在现代生活中，我们有许多发明。
In the early nineteenth century, people began to use gas (gaslight), but the gas pipeline supply by a leak or blockage, very easy to have an accident, people for illumination of reform, very ardent. In fact, Edison for himself set the mission impossible: in addition to improve lighting, but also of Thomas Edison electric light Create a set of power supply system. And he and the dream LuoYuan buddies, sleepless do 1600 repeatedly heat-resistant material and more than 600 plant fiber experiment, only produced the first carbon wire bulb, can a burning 45 hours. Later he more on this basis, the method of continuous improvement manufacture can ignite 12 hours finally came out with the ZhuSi bulbs. The 19th century the 1980s, Edison electric light career succeeded, this success than any previous achievements brought him reputation. In the 1980s, before he had little mistake, intermediate later, although he has made great achievements, but also common occurance of failure. Edison's most not commendable actions is one of his criticism alternating current, say it has side effects, likely cause of death and injury, but he did not add details. So somebody said, "as he such a mess out many inventions that people about others' new invention saurday attack, this is very contradictory things." He opposes the use of alternating current and direct current, so the approve a fierce debate and stubborn in failure. In this respect, reflects the Edison became a celebrity after the stubbornness of started to foster old-fashioned shortcomings.3、I will invent a time machine in the as it 's been my dream in my life. Time machine allows people to travel back in time to prevent disaster to happen. It also allows people to tavel into dinstant future to find out solution for Incurable illness including cancer and aids. However, this machine may be abused by people to create chaos in our world or even completely change our history. Therfore, security features are essential for my invention. The future invention of time machine will definately bring more advantages for human being.我会因为它是我的梦想在我的生活中，发明时间机器。时间机器允许人们旅行回来的时间来防止灾难的发生。