《大学英语（一）》课件-【思政课件】Four Great Inventions

FourGreatInventions四大发明学习目标1.了解古代的四大发明2.体会四大发明带给世界的影响第一部分了解古代四大发明PartOne:UnderstandingthefourGreatinventionsofancienttimesTheinventionofmovable-typeprintingisagreattechnologicalrevolutioninthehistoryofprinting.Themethodofmovabletypeprintingistomaketheyang-weninversemodelofasinglecharacter,thenselectthesinglecharacteraccordingtothemanuscript,arrangeitinthefontplate,inkprinting,andthenremovethemodelafterprinting,andleaveittobeusedagaininthenextprinting.活字印刷术的发明是印刷史上一次伟大的技术革命。活字印刷的方法是先制成单字的阳文反文字模，然后按照稿件把单字挑选出来，排列在字盘内，涂墨印刷，印完后再将字模拆出，留待下次排印时再次使用。活字印刷术司南PapermakingisoneofthefourgreatinventionsofChina.IntheWesternHanDynasty,peoplealreadyknewthebasicmethodofmakingpaper.IntheEasternHanDynasty,theeunuchCAILunsummeduptheexperienceofhispredecessors,improvedthepapermakingprocess,andusedplantfiberssuchasbark,hemphead,ragsandoldfishnetasrawmaterialstomakepaper.Thequalityofpaperwasgreatlyimproved.Thispapermaterialiseasytofind,cheapandeasytopromote.Sincethen,theuseofpaperhasbecomemoreandmorecommon.Papergraduallyreplacedsilkandbecameawidelyusedwritingmaterial,whichalsofacilitatedthecirculationofclassicalbooks.造纸术，是中国四大发明之一。西汉时期，人们已经懂得了造纸的基本方法。东汉时，宦官蔡伦总结前人经验，改进造纸工艺，用树皮、麻头、破布、旧鱼网等植物纤维为原料造纸，纸的质量大大提高。这种纸原料易找，价格便宜，易于推广。此后纸的使用日益普遍，纸逐渐取代简帛，成为人们广泛使用的书写材料，也便利了典籍的流传。火药，又被称为黑火药，由硝酸钾、木炭和硫磺机械混合而成。是在适当的外界能量作用下，自身能进行迅速而有规律的燃烧，同时生成大量高温燃气的物质。Gunpowder,alsoknownasblackpowder,isamechanicalmixtureofpotassiumnitrate,charcoal,andsulfur.Undertheactionofappropriateexternalenergy,itcancarryoutrapidandregularcombustionandgeneratealargenumberofhigh-tempe