英语科技文8篇

1.《蚕丝制作》

As is displayed in the first diagram, the life cycle of the silkworm can be categorized into 4 main stages. First, the life of the silkworm starts from eggs propagated by the moth, and it takes 10 days for each egg to become a silkworm larva that feeds on mulberry leaves. Silkworm larva continues to grow in 4 to 6 weeks, then wrapping itself with silk thread to construct a cocoon in the next 3 to 8 weeks. A moth can be produced from the cocoon in 16 days. The life cycle begins again from then on. Focusing on the second diagram, it illustrates the 5 main steps of the procedure of producing silk cloth. Well generated cocoons will be selected firstly. Before the silk thread can be unwound, cocoons have to be boiled in hot water. One cocoon can produce approximately 300 to 900 metres of silk thread. The unwound thread will be dyed afterwards to be weaved into silk cloth. Overall, the two diagrams reveal the stage of producing cocoons in the life cycle of the silkworm can be used to make silk cloth through 5 simple steps.

2.《户外取水》

The chart describes how water is obtained outdoors. According to the figure, the first step of obtaining water outdoors is to find a hole with green plants on its bottom. Next, remove the green plants in the middle and put a container there. Then, cover the hole with a plastic sheet and place two stones on both ends of it to secure its position. A third stone is laid on the middle of the plastic sheet so that the middle part is also the lowest part. When the sun shines on the green plants in the hole, water evaporates from these plants. The vapor rises up and then cools down to form water drops on the plastic sheet. When there is more and more water, it flows along the sheet to accumulate on the lowest part. Finally, water falls down into the container directly under the middle stone. Thus, water is collected successfully through evaporation from green plants.

3.《房屋不同季节的构造》

As is displayed in the flow chart, the principles of insulation in cool and warm climate respectively differ to a large extent. As to the situation of cool climate, we adopt the high-angled roof in order to be nearly parallel with the direction of the sun so that the direct exposition to the heat of sun is lessened as much as we can. By this, the temperature of the material won’t fluctuate within a large range. Meanwhile, thermal building material could enhance the heat storage insulation, preventing outflow, thus reduction of heat. Adversely, in warm climate, reflective building material is indispensable with overhands for shade. The direction of the roof is almost vertical to the direction of the sun to lead to external insulation reflection. By this, ventilation would result in the removal of heat storage rather than reduction. Through the different working principles of ventilation, we are fascinated by the masterpieces of modern science and technology.

4．《超市建造地点选择》

As is unfolded in the map, Place M and N have their unique pros and cons as to the place for building the supermarket. First of all, Place N is located in the urban area of the G town, which may have more population and business. This advantage is incomparable with Place M. What’s more, Main road runs across the center area with convenience in traffic and logistics for the market afterwards. However, the place is equally far away from the neighborhood and the suburb area and cannot attract the residents in

the outskirts. As a double-edged sword, Place M is more specifically customer-oriented. In spite of its comparably remote location with Place N, it would attract more customers in the outskirts, for they are reluctant to make a long trip for shopping. On the other hand, the train line nearby will also bring convenience in traffic to the urban-dwellers. Situated to the north-west of Place N, Place M is near the A and B Town with total population of 23 million, far outnumbering the overall population of D and E town, with 12 million. What’s worthy of being mentioned is that fierce competition in Place N and probable monopoly in Place M should also be taken into account when building the supermarket.

5.《玻璃的再生》

As is displayed in the flow chart, the recycling process of glass is really a complex one. The overall process can be categorized into 3 stages. First, glass products in various forms are gathered in the Collection point, so that they are easily transported by special trucks or vans to the Cleaning plant, where they get sterilization by high-pressured water. There are three different channels in the Recycling plant, namely Brown, Green and Clear, which represent the colors of glass. After recycled in the furnace, glass products are melted into recycled liquid glass. Mixed with new liquid glass, the compound is finally moulded into solid glass, which, afterwards, will be sent to various customer supermarkets for selling. Thus, the glass will go to the customers for different purposes. Through a brief introduction of the circle of glass recycling, we come to realize that recycling plays a vital role in environmental protection and ecological preservation.

6．《化肥的制作》

As is shown in the flow chart, the process of recycling organic waste to produce compost is really a complex one. The whole process can be categorized into five stages. First of all, prepare a plastic container which has four holes for ventilating the air. There is a rule when putting waste into the container, food at the bottom within 15 centimeters high, grass at the middle and newspaper at the top within 15 centimeters high altogether, in order to make a optimum environment for different bacteria reproducing. In the following stage, we can witness nitrogen and water being put into the container. What's worth mentioning is that water is only added in a hot weather. Next, heat the waste and let the bacteria reproduce fastly, with which the organic waste can be decomposed and became garden fertiliser after 6 months. Subsequently, we can carry the compost out and move it to the garden, thus a new recycling can begin. In conclusion, using this way to turn the organic waste into garden fertiliser is environmentally friendly. By enlarging the number or volume of the container, we can dispose more waste at the same time.

7．《咖啡的制作》

The diagram shows the stages in the process of making chocolate. Chocolate comes from the cacao tree, which is grown in parts of South America, Africa and Indonesia. The tree produces large red pods which contain white cocoa beans. Firstly, when the pods are ripe, they are harvested, the beans are removed

and they are fermented for several days in large wooden boxes. During the fermenting process, the beans turn brown. Next, the brown beans are spread in the sun to dry. They are then put in large sacks and transported by train or lorry. After this, the beans are taken to a chocolate factory where they are roasted in an oven at temperatures of between 250 and 350 degree Celsius. After being roasted, the beans are crushed and the outer shell is removed. This part is not needed for making chocolate. Finally, the inner part of the bean is pressed and liquid chocolate is produced.

8. 《砖块的制作》

The process by which bricks are manufactured for the building industry can be outlined in seven consecutive steps. First the raw material, clay, which was just below the surface of soil in certain clay-rich areas has to be dug up by a digger. Then the lumps of clay are placed on a metal grid in order to break up the big chunks of clay into much smaller areas, which fall through the metal grid onto a roller, whose motion further segregates the bits of clay. Sand and water are added to make a homogenous mixture, which is then either formed in moulds or cut into brick-shaped pieces by means of a wire cutter. Those fresh bricks are then kept in a drying oven for at least 24 and a maximum of 48 hours, several dozens if not hundreds of bricks at a time. The dried bricks are then transferred to a so-called kiln, another type of high temperature oven. First they are kept at a moderate temperature of 200 ℃ -1300 ℃ . This process is followed by cooling down the finished bricks for 48 to 72 hours in a cooling chamber. Once the bricks have cooled down and have become hard, they get packaged and delivered to their final destination, be it a building site or storage.