英语五分钟演讲PPT-- lotus effect

1、 X-Effect OBAMA“Live in the silt but not imbrued”.In chinese,we say:出淤泥而不染出淤泥而不染Lotus is a symbol of purity in several Asian religions, because it is pure.Pure Like these ? Pity !They are just pure in different way Actually ,In modern society ,STAYING “PURE” is becoming more of a CHALLENGE for human

2、 beings under the influence of so many temptations. BUT for the lotus , KEEPING PURE is justa piece of cake.But, how?The major reason for this might be the : Self-cleansing property and superhydrophobicity of its leaves.(叶子的自洁性和超疏水性叶子的自洁性和超疏水性)To better understand it, we should know this : Then ,wha

3、t is the situation of a water drop on a lotus surface?Specifically ,its like this :在表面张力作用下，水与超疏水表面會有一接触角在表面张力作用下，水与超疏水表面會有一接触角(contact angle)A water drop on a lotus surface showing contact angles of approximately 147.Why is lotus 90? Special structure of its leaves can explain more The epidermis of

4、 the lotus plant possesses papillae with 10 to 20 m in height and 10 to 15 m in width on which the so-called epicuticular waxes are imposed. These superimposed waxes are hydrophobic（疏水的）（疏水的）. （莲类植物的表皮具有10-20微米高，10-15微米宽的乳头结构，上面附着着所谓的表皮下蜡质颗粒.这些附带的蜡质是疏水的）具有微米级角质层（micron-grade cuticula）与纳米级蜡质洁晶(nano-g

5、rade epiticular waxes)莲叶表面Computer graphic of a lotus leaf surface. This structure enables the contact area and the adhesion force between surface and droplet to be significantly reduced . (这种结构使得液滴和荷叶表面之间的接触面积及粘附力显著降低，从而导致荷叶的自洁过程。) The hydrophobicity (疏水性疏水性)of a surface is related to its contact a

6、ngle （ ）. The higher the contact angle the higher the hydrophobicity of a surface. Plants with a double structured surface like the lotus can reach a contact angle of 170 whereas a droplets actual contact area is only 0.6%. All these leads to a self-cleaning effect.A comparison细微结构与自洁作用即使同样具有疏水性的表面，

7、在细微结构与自洁作用即使同样具有疏水性的表面，在细微结构上细微结构上的水珠的水珠会会吸附吸附着着灰灰尘颗粒滚动尘颗粒滚动，而在，而在光滑表面上光滑表面上，水珠能使，水珠能使颗颗粒粒移动移动的程度有限的程度有限And I hope you understand the lotus “living in the silt but not imbrued” better.Because The more You understand it ,the more you understand X-Effect Thats all for my topic.Thanks for your patience

8、.Extra 莲花叶子表面上的化学组成：由腊质组成的角质层和100200奈米的微毛结构构成了莲叶表面。也就是说微毛的构造使液体接触莲叶的表面是一种混合的介面-部分为固态的叶面；部分为孔隙中的空气，若是透过高倍率的电子显微镜来观察：会发现一旦水滴落到莲叶上，水珠都是由凹凸不平的表面中凸起的腊所顶住，这很像是一个人躺在针床上，想要舒舒服服躺平是不可能的，只有卷起身子有如球形的处在针床上。如此一来水珠无法稳定的停留在莲叶上，一旦稍微有气流，即能将水珠吹走，所以说莲叶具有拨水的特性。另一方面，由于奈米级的微毛间距，也使得污垢在莲叶上的接触面只在这小小的顶尖上而已，当水滴滚动过去时，不但水滴会被移走也会

9、顺便将附着在上面的灰尘、污垢跟着带走，这便是莲叶自我清洁的特性。难怪古代文人称赞花中的君子莲花出淤泥而不染！ 莲花具有很多小凸起状的角质层和腊质形体。图片中棒形的尺度大小莲花具有很多小凸起状的角质层和腊质形体。图片中棒形的尺度大小(当比例当比例尺用尺用)为为20微米。微米。 空气被封于液体与叶面的凹处中，减少了液体与叶面的接触面积，产生了具空气被封于液体与叶面的凹处中，减少了液体与叶面的接触面积，产生了具强烈疏水性质的表面。棒形的尺度大小强烈疏水性质的表面。棒形的尺度大小(当比例尺用当比例尺用)为为20微米。微米。叶面上的液滴，当其滚动时，便会吸附起叶面上的污染粒，带离叶面。此图说明叶面上的液

10、滴，当其滚动时，便会吸附起叶面上的污染粒，带离叶面。此图说明了莲花效应。棒形的尺度大小了莲花效应。棒形的尺度大小(当比例尺用当比例尺用)为为50微米。微米。This effect can easily be demonstrated in many other plants, for example Tropaeolum (nasturtium), Opuntia (prickly pear), Alchemilla, cane, and on the wings of certain insects.Tropaeolum旱金莲旱金莲Opuntia 羽衣草属羽衣草属 ( Alchemilla

11、)Application of lotus-effectClothing industry防水，防尘，不用洗啦！防水，防尘，不用洗啦！ 汽车的前挡玻璃（不用雨刷了） 摄像机的镜头（防水，防尘）Coating industry(涂料产业涂料产业) This self-cleaning surface characteristics not only exist on the lotus leaf surface, also have been validated in animal skin or other plant leaves, and self-cleaning function of

12、 the hydrophobic coating, coating technology process development counterfeit lotus, is unmistakable trend.Related research directions include:(1) used in LCD products of high gas, high transparent coatings and anti-reflective high hardness coatings(2) applied to electronic products of electromagnetic shielding coatings(3) used in the construction of energy-saving insulation coatings and self-cleaning coatings(4) metal corrosion-resistant anti-rust coating(5) the environmental compatibility of the coating(6) with a germicidal effect nan