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In this video we are going to study deeply good. Good was a very important

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material, technical material in the past because there were a lot of trees, a lot of

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forests, so nowadays good is not so important because there are a lot of

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of materials which properties are better than wood but nowadays the beauty of wood is very very

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important to do for example furniture so the the most important application of good nowadays is as

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as a material for the furniture. In the past it was important in houses and so on but today is more

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important in furniture. Well, we are going to study all these different things. This is the index of

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this unit. First of all, the raw material to prepare good is obviously

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trees. Trees are autotrophic items. This means that they can transform inorganic

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material matter into organic matter and to do this they need a the chlorophyll

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that they usually have in a green leaves so it's necessary to move the inorganic

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matter which is in soil, from soil to the leaves in the crown of the trees and to do this they

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usually use the trunk and we use the trunk to get good. The trunk has different parts. It has

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the pit which is the most inner part of the trunk and the bark which is the outer part of trunk.

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And between the bark and pin we have hilt wood and shaft wood which is the part of the trunk

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that usually used to do and to to get a wood from this part of the trees well to

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do the forest exploitation is important that we we do a selective and a

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geological of logging in our forest because if we do this part this first

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step perfectly we help to the forest to renew it, but if we do in a bad way it

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could be a disaster. So this is the the most important and most critical step of

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the forest exploitation. And after that we need to remove all the branches and

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and the upper crush, and then chop the logs, transfer to the sun windmill, and there we

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need to cut in, ground in, and do a surface filling.

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Well the cutting of the goods and of the trunks can be in different ways as you can see in

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this slide.

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the resistance, the mechanical resistance, is not the same in the different directions of the

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track. That's the main reason why, depending how we do the cutting, the result of this material

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has different mechanical properties. But in any case, obviously, the mechanical properties are

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different in different directions also you can have different shapes to good

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different thickness plain plain shape different thickness or a square or so

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one depending what what are going to to make with this this material

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so we have a difference not only not only have well good can be classified into two different

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types, which are natural and artificial or sometimes is also called engineering good.

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In engineering good there are three types of engineering good, of artificial good.

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One is plain, is made using different very thin plain that can be in different types.

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The more important are play goods.

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The other are agglomerates, which are made by different drops or similar of goods.

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Another is tablets, which is made from different pulp and is object to different hybrids.

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We can see the natural good can be soft or hard.

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You have some examples of one of these.

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Soft good usually is to materials that has leaves that are always in all the seasons.

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They don't change, they don't lose their leaves in winter or in autumn.

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And hardwood usually is from these trees which loses its leaves in autumn.

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As you can see here, for example, very important can be pine as a soft wood and cherry for

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a hard wood.

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They usually used to do different types of furniture.

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Here you are the different properties of hardwoods and sun example.

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It's very important type of wood.

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Shot wood are also important and if the soil is also have for example pine.

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they they would have different properties and different applications and its applications

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is connected to its properties obviously and they are very important to do from to do part

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of a houses and structures because it has a very good resistance to compress so they

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sometimes are used in in this way as part of a structure of construction and

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they also are low density and because of this they usually they can be used to do

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for example, floats and ships and different parts of the ships, for example.

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Because it has low electricity and thermal conductivity, they can also use as insulators

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of this physical phenomena, for example in houses, you can use the wood to cover the

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walls and to insulate a thermal cow from heat, from losses of heat.

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They are composed, gout is a mixture of cellulose and lignin.

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The lignin gives rigidity to the goods, meanwhile the cellulose gives the structural part.

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So if you can, in any way it is organic matter.

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So in any way it can be used to burn and to get energy from its burns.

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But it also can be used to get paper.

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If you eliminate the lignin, it is just only cellulose, so this is part of paper.

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This is the process to get paper.

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It's important because you chop it and then you use some chemical products to eliminate

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the lignin from the gul and to change its color to get this white color this is the

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reason why this kind of industry is so unfriendly in an environmental way they use a lot of

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water and they usually contaminate this water, so because of this we try to reduce this contamination.

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In any case, the last part is a calendar in which you can get different papers.

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And this is all for today.