Speaking of eme- part 2
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- Điều hướng trang này:
- Thermosetting plastics
In this table I can see 3 kinds of MATERIALS. They are ABS, Acrylic, Nylon. ABS has high impact strength and toughness. It is scratch-resistant, light and durable. It is used to make safety helmets, car components, telephones, kitchenware. Acrylic is Stiff, hard, very durable and clear. It can be polished easily. It Can be formed easily. It is used to make Aircraft canopies, baths, double glazing. Nylon is Hard, tough, wear-resistant and self-lubricating. It is used to make Bearings, gears, casings for power tools. That is all the information about the 3 kinds of MATERIALS that I know
In this table I can see 3 kinds of MATERIALS. They are Epoxy resin, Polyester resin, Urea formaldehyde. Epoxy resin has High strength when reinforced. It is good chemical and wear- resistance. It is used to make Adhesives, encapsulation of electronic components. Polyester resin is Stiff, hard, brittle, Good chemical and heat resistance. It is used to Moulding, boat and car Bodies Urea formaldehyde is Stiff, hard, strong, brittle, heat-resistant, and good electrical insulator. It is used to make Electrical fittings, adhesives. That is all the information about the 3 kinds of MATERIALS that I know Unit 4 The above paragraph gives us some information about metals, alloys, their uses and heat treatments. There are 3 main materials (metals, concrete, plastics) and 3 kinds of heat treatment (hardening, which is used to make metals harder; tempering, which is used to make metals softer and less brittle; annealing, which is carried out to make a metal soft). Metals have high strength and tough. Concrete is usually used in construction but the steel core is still the bearing part and concrete is cheaper. Plastic is the lightest in these 3 materials. Its property is good corrosion-resistance. The metals can be recycled but plastics can only be dumped or burned. => In life, these materials and kinds of heat treatment have many applications. Metal and hardening are used to make knives. Uses of plastic are as household appliances, details of a car or motorcycle, insulating equipment... Not only in traditional construction, concrete is also used to make furniture, decorations or imitation stone concrete. The bar graph illustrates the differences in iron production in four countries: Australia, the US, Canada and Chile. Looking at the chart, I can see that the largest production belongs to Australia, accounting for 85 million of tones. The country is also home to the world's largest reserves of crude iron ore. As a resource exporter, Australia leads the world in reserves and output. In contrast to Australia, Chile has the least total production in the ranking. The whole country accounts for only 30 million tones. The US and Canada accounted for 59 and 40 million tones, respectively, ranking 2nd and 3rd in the table. That's all for iron production in four countries, and these numbers are constantly growing, so these data may not be current. In the chart I can see the production of tin in millions of tones, In four contries: Australia, USA, Canada and Chile. Australia produces the most tin and USA produces less tin than Australia about 25 millions of tones. USA produces a little more tin than Canada about 20 millions of tones. Australia produces a lot more tin than Chile about 52 millions of tones. Chile produces the least tin. That is all the informations about production of tin in millions of tones. The bar graph illustrates the differences in iron production in five countries: Malaysia, Bolivia, Thailand, Indonesia and China. Malaysia is one of the few country in the world which is endowed with a vast reserve of good quality tin ore. So malaysia's tin reserve is at the top with 60 thounsands tons. The precious tin ore resource provides a strong base for the development of metallurgical industries in this country. Bolivia produces less tin than Malaysia about 20 thousands of tones. Thailand produces a little more tin than China about ten thousands of tones. Úc là một trong số ít quốc gia trên thế giới được thiên nhiên ưu đãi với trữ lượng lớn quặng sắt chất lượng tốt. Nguồn tài nguyên quặng sắt quý giá là cơ sở vững chắc cho sự phát triển của các ngành công nghiệp luyện kim, => In the world, minerals are very valuable resources and so is tin. Tin is widely used in industry (details of machines, surfaces that are plated with tin will resist oxidation), food processing (food box, drinking water cans), metallurgy (some alloys are made up of copper and tin or tin and lead)… In the chart I can see the production of tin in thousands of tones, In Five contries: Malaysia, Bolivia, Thailand, Indonesia and China. Malaysia produces the most tin and Bolivia produces less tin than Malaysia about 20 thousands of tones. Thailand produces a little more tin than China about ten thousands of tones. Malaysia produces a lot more tin than China about 40 thousands of toné China produces the least tin. That is all the informations about production of tin in thousand of tones. Unit 5 In the picture, I can see five things. They are scissor, plier, foot pump, paper trimmer and water tap. First, the scissor and pliers works based on the principle of levering. Second, the foot pump and paper trimmer works based on the principle of reciprocating. Finally, the water tap work based on the principle of rotating. That is all the information about simple mechanisms that i know Unit 6 I can see the simple DC motor consists of 2 main components. They are a field magnet and an armature. The armature is placed between the poles of the field magnet. It consists of a loop of wire and a commutator. The loop is connected to the commutator. The commutator is placed in front of the armature. It reverses the current to the armature. The brushes current the motors . That is all the information about a simple DC motor that i know. tải về 495.93 Kb. Chia sẻ với bạn bè của bạn:
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