1. Why is the trunk round?

In the process of observing nature, I happened to find that the shape of the trunk is almost round-an empty cone. Why is the trunk conical? What are the benefits of a conical trunk? In order to discuss these problems, I made more in-depth observation and analysis.

With the help of my tutor, I consulted relevant materials and learned that the stems of plants have the functions of supporting plants and transporting water and other nutrients. The stems of trees are mainly composed of vascular bundles. The supporting function of stem is mainly borne by wood fibers in xylem. Although the stems of woody plants will become thicker year by year, in a certain time range, the number of woody fibers in the stems is certain, that is, the cross-sectional area of the stems is certain. Then, based on the assumption that the cross section of the trunk grows into different shapes, we design experiments to explore the reasons and advantages of conical trunk.

Through experiments, we find that when the cross-sectional area and length of (1) are fixed, the vertical supporting force of triangular columnar objects is the largest and the lateral bearing capacity is the smallest; The vertical supporting force of cylindrical objects is not as good as that of triangular cylindrical objects, but the lateral bearing force is the largest; (2) For trunks with the same mass and different shapes, the short conical trunk bears the largest wind force; (3) Wind is a natural phenomenon, which affects the cross-sectional shape and height of trees. The approximate cone-shaped trunk has a low center of gravity, and the huge root system is connected with the earth, so the center of gravity drops lower and the stability is greater; (4) The cross section of the trunk is round, which can reduce the damage, has stronger mechanical strength and can resist the wind attack. At the same time, under the action of the wind, the bending degree of the trunk is similar everywhere. No matter which direction the wind blows, the resistance of the trunk is similar, and the trunk is not easy to be damaged.

The above experiments reflect the laws of nature, and nature enlightens us: (1) A columnar object with a triangular cross section has the greatest vertical supporting force, and its shape can be used in buildings, such as angle steel; (2) A circular object with a circular cross section has the largest lateral bearing capacity, and similar building materials can be found everywhere, such as TV towers and telephone poles.

In the process of observation, experiment and analysis, I gradually explained and revealed the mystery of conical trunk, increased my knowledge, and combined my knowledge with practice, which not only consolidated my knowledge, but also improved my interest in learning, and initially learned the scientific observation and analysis methods.

2. How to write a scientific paper

Since 1982 was held in Shanghai, the national youth invention and science seminar has been held every two years. Up to now, it has lasted for 10 (renamed as the National Youth Science and Technology Innovation Conference from the tenth session in 2000), and it has become a traditional project of science and technology activities in primary and secondary schools and an important part of school education. Many students' excellent works have been published in national newspapers and periodicals, and some have won prizes in the country and even internationally!

1. What is a scientific paper?

Some students regard writing small scientific papers as mysterious, and think that it is a matter for scientists, which is unattainable for us children. This is a complete misunderstanding. Students can not only write, but also write high-quality papers.

Scientific papers written by scientific workers refer to scientific research reports written by the author through experiments, observation and other means, and then through analysis and research according to the scientific research projects and determined scientific research topics. The scientific papers written by students are shorter and shallower than those written by scientists.

In fact, a scientific paper is a written summary of the achievements made by students through scientific observation, experiment or investigation in extracurricular scientific activities. Its manifestations are various: it can be a conclusion drawn after careful observation and in-depth thinking about something; It can be the conclusion of analysis after hands-on experiment; It can also be a summary after a local investigation; You can also draw conclusions through logical reasoning. ...

So, are there any quality standards for scientific papers? Yes It must have "three characteristics".

1, science. Scientificity is one of the important characteristics that distinguish scientific papers from other genres, and it is the life of scientific papers. It requires scientific topics, correct research methods, conclusive arguments, reasonable and logical arguments, and concise and accurate words.

2. Creativity. The topic selection and main viewpoints of small papers should have their own new discoveries and unique opinions, which have certain practical significance to people's production and life. The same small paper has not participated in scientific seminars at all levels, nor has it been published in newspapers at all levels. Of course, if you further study on the basis of other people's research, it is also feasible and creative to put forward novel, unique and fully demonstrated views.

3. practicality. The title of the paper must be discovered by the author himself in scientific exploration activities; The arguments supporting the main points must be obtained by the author through observation, investigation, experiment and other research methods, and have practical basis; The paper must be written by the author himself. There can be no signs of fabrication, speculation or adult substitution.

The above "three natures" are the quality standards for measuring scientific papers. If you write Sunflower, although your observation is meticulous, your posture description is vivid and your character analysis is perfect, if you can't get a scientific and meaningful conclusion, it can only be regarded as a good essay or observation diary, not a scientific essay.

Writing scientific papers is a very hard work and a very meaningful activity. Success belongs to young friends who are brave in exploration and unremitting pursuit!

Second, the types of scientific papers

The most common forms of scientific papers are scientific observation papers, scientific experiment papers, scientific investigation papers and scientific explanation papers.

Scientific observation paper

Scientific observation essay refers to teenagers' careful observation of something or a natural phenomenon, careful analysis and comprehensive study of the obtained materials and data, and then draw conclusions and make scientific explanations and descriptions.

Liao Hao's father in Hunan often coughs. Through long-term and repeated observation, he found that the wind direction has a very close relationship with his father's cough, and found out the "culprit"-a large amount of smoke from the chimney of Hunan Rubber Factory, which contains sulfur dioxide. My father has a throat allergy and a reflexive cough when he smells it. His essay "Dad's Cough" mainly draws a conclusion by observing this research method, which belongs to scientific observation prose and won the third prize of the second national youth science seminar.

It should be noted that the research object in scientific observation essay is an objective natural thing or phenomenon, which occurs under the condition of natural light and is not controlled by human beings, so the content described in this paper should be the object, process, conditions and various phenomena observed by the author, and no artificial conditions or personal prejudice can be attached. In addition, observation is a long-term, systematic and repeated activity, which requires the patience, meticulousness and perseverance of the author.

(2) Small scientific experimental papers

Essays on scientific experiments, sometimes called "experimental reports", are articles that teenagers create specific conditions for the research objects, analyze the obtained materials and data after repeated experiments, and draw comprehensive conclusions. It focuses on the objective description of the experimental process and the scientific explanation of experimental phenomena.

Parthenocissus can climb the wall, which is known to many students. But why can Parthenocissus climb the wall? Xiong Bin, a student in Wuhan, found through observation that this is related to the "tentacles" of Parthenocissus tricuspidata. Then he estimated that there were 25 "tentacles" attached to the wall on the average one-meter-long stem of Parthenocissus tricuspidata, and made an experiment of "measuring and adsorbing the tension of tentacles". The purpose of the experiment is clear, the experimental steps are detailed, the data are accurate and the explanation is strong. The conclusion is true and credible, and it is an excellent scientific experimental paper.

(3) A short paper on scientific investigation

If you want to study the pollution degree of a certain water area closely related to people's lives, the air pollution source in a certain place, and find out the evolution process of a strange mountain, the animal and plant resources and distribution in a certain range, you have to make a field trip. A small paper written through investigation, interview and field investigation is called a scientific investigation small paper. Sometimes it is also called "scientific investigation report" and "scientific investigation report".

In the article "Evergreen Water of Zhushengtian Reservoir", which won the first prize in the 5th National Youth Science Symposium, the author made a field investigation on the geographical and ecological environment and water storage capacity of the reservoir, and made a field measurement as far as possible, found out the hidden dangers of the reservoir and put forward more reasonable suggestions. This paper expounds the time, object, content and conclusion of comprehensive analysis, and draws the "rain collection map of Shengtian Reservoir" and "schematic diagram of strong erosion in Zhongshan", plus some actual data, so that readers can have a more comprehensive and clear understanding of the investigation object.

When writing a small paper on scientific investigation, it is sometimes specimens or photos of animals, plants, rocks, soil, etc. It should be attached to the text to enhance persuasiveness.

(D) scientific explanation essay

Scientific interpretation prose refers to a kind of prose in which the author uses accurate and reliable information to explain and explain a natural phenomenon or thing. Generally speaking, it does not directly adopt research methods such as observation, experiment and investigation, but mainly obtains rich second-hand information from books, periodicals and teachers, and expounds a certain point of view in a language it understands through its own comprehensive analysis and logical reasoning.

"Why Guiyang is the Second Spring City of the Motherland" is a small paper that won the third prize of the Second National Youth Science Seminar. The author's research methods have their own characteristics. First, insist on using radio and television records to sort out the weather and temperature in Guiyang and Kunming; Second, using the ready-made scientific research achievement "China Climate Atlas", find out the representative temperature situation in Chongqing and Beijing and compare it with Guiyang and Kunming; The third is to verify the average temperature of Kunming and Guiyang in June, April, July and June, and then draw a conclusion through comprehensive analysis.

Although this kind of articles are not supported by the first three personal practices, they put forward new ideas and opinions through careful collection and comprehensive analysis by the author, so they are also recognized as scientific essays.

I want to remind you in particular, to write a short scientific explanation paper, and never ask a question and look up the information in a hurry, and then write it down without analysis. Such an article without new ideas and new insights can only be regarded as a general popular science article, not as a scientific essay, and it can't cultivate your ability to study problems.

Third, the topic selection of scientific papers

The first step in writing a short paper is to determine the research object and consider what problems to study. This is the topic. Some people say that choosing a good topic is equivalent to completing half of a small paper, which shows the importance of choosing a topic for a small paper.

Some students said that there are too many wonderful phenomena in nature. What should we study? Some students said that I was used to seeing everything in nature and found nothing novel. Besides, what I want to study has already been studied by others, and it doesn't make much sense to write it.

In fact, as long as you understand the basic principles of topic selection, master several common methods of topic selection, and be a serious and responsible person in your daily study, life and scientific and technological activities, you will certainly find topics worth discussing.

There are many ways to choose the topic of scientific papers, and individuals can choose according to different situations. The following are some common methods of selecting topics for students' reference.

1, accidental discovery method. One Sunday, Songzi's classmate Hu Changcheng was playing in the ditch behind the house. There are many tadpoles swimming around in the ditch. Suddenly, he found a little tadpole swimming alone, as if it were out of place with other tadpoles. He used twigs to pull the tadpoles out of the group into groups of tadpoles, and soon it swam alone again. He was surprised, so he and several other groups of tadpoles were put in bottles and kept at home for observation. Finally, the unsociable tadpoles became frogs, and the others grew into toads. Through long-term observation, it made clear the difference between the frog and the toad's youngest son and wrote an excellent article.

This kind of topic is not considered in advance, but only interested in the fleeting phenomenon discovered by accident, so as to seize it and seek the source.

2. Classroom extension method. In the primary school science class "Animals and Environment", students studied the relationship between earthworms and light, temperature and humidity, and found that earthworms like dark, supermarket and warm environment, and learned to experiment with the difference method to judge the wrong causal relationship. After class, you can study the living environment of centipedes, crickets, ants and other small animals with the methods you have learned. You can continue to study other mysteries of earthworms: for example, does earthworms have eyes? Can earthworms open their ears? Earthworms' regeneration ability, soil loosening ability, etc.

3. Question inquiry method. The little fly is really annoying, it is the chief culprit of infectious diseases! But he's really weird. He often comes into contact with all kinds of bacteria. Why doesn't he get sick?

Sleeping can relieve fatigue and restore energy. Do fish who wander leisurely in the water all day sleep?

……

In daily life and study, you will definitely have some questions you don't understand. Can you use it as the research object of your thesis?

Mao Dengsheng, a fifth-grade student in Daoxian County, Hunan Province, was playing with some classmates in the bamboo forest near the school one day, arguing endlessly about whether the bamboo was empty or what was in it.

Careful Mao Dengsheng has always kept this problem in mind. After school, he consulted materials and did experiments, and concluded with a lot of evidence that bamboo is not empty, but contains air, oxygen, nitrogen, carbon dioxide and other gases. Based on this, the essay "What's in Bamboo" won the first prize of the first national youth scientific essay contest.

4. Teacher guidance method. If you have a small animal or some flowers, but don't know where to start, you can find a teacher to choose a topic according to your actual situation and conditions.

If you join the school's science and technology group, you can tell the teacher the idea of the research and let the teacher determine the research topic, and then you can observe and experiment around the topic.

For example, under the guidance of teachers, students from the Biology Group of Chongqing People's Primary School have selected some research topics, completed many small papers such as Investigation on the Characteristics of Yellow Horned Trees in Chongqing and Evergreen Water in Zhushengtian Reservoir, and won the first prize of the National Youth Small Paper for many times.

5. Scientific verification of idioms and proverbs. Most idioms are created by people in their long-term social life and practice, but some of them come from fables, folklore and established ones. A few of these idioms do not necessarily conform to the objective reality. It can be analyzed and verified by scientific methods.

Everyone is familiar with the idiom "a drop of water wears away a stone", which means that a drop of water can wear away a stone. This is a metaphor. As long as you persist, you can do seemingly difficult things even if your strength is small. But common sense tells us that "water drop" is just a drop of liquid. Its strength is very small, and the impact speed will not be too fast. How can it go through hard rock? Members and students began to doubt the scientific nature of this idiom, and verified the scientific nature of this idiom by doing simulation experiments and consulting materials.

"Spring breeze blows the east wind, and our ancestors get wet" is a well-known meteorological proverb. A classmate made a detailed observation record of the temperature, wind direction and weather in March, and then obtained the application scope of this proverb by using scientific statistics, which provided a reference for meteorological forecast.

Is it still false to "sunflower blossoms to the sun"? However, Jiang Linbo, a Hunan native, challenged this theory. Through two years' experimental observation, he came to the conclusion that "Sunflowers don't always turn to the sun" and "Sunflowers turn with the sun should refer to the bud stage, and don't move after flowering".

From this point of view, even if it is a long-recognized conclusion, we should study it carefully and don't follow suit. Only in this way can we innovate.

It is particularly important to note that subjective and objective conditions should be considered when choosing a topic. As the saying goes, "know yourself and know yourself, and you will win every battle." When choosing a topic, you should know what your strengths and weaknesses are, whether you are interested in the research problem, whether you have the ability to study clearly, whether you have reached this level of knowledge and understanding, whether you have the perseverance to complete this topic, and whether you have experimental equipment and venues to study this problem.

If you finish the topic of "Exploring the Mystery of Snakes", you must master the basic knowledge about snakes, have the ability to catch snakes, be able to distinguish poisonous snakes from non-poisonous snakes, and master the rescue methods of being bitten by poisonous snakes. In addition, it is necessary to have equipment for raising snakes. Otherwise, it is better to change a topic that is more in line with subjective and objective conditions.

Fourthly, the selection and analysis of small papers.

After the topic is determined, the materials can be selected and analyzed. The specific content is to make a research plan, collect and sort out data, conduct in-depth field visits, conduct observation experiments, analyze various materials and draw conclusions.

material

1, direct observation. It is a way for people to observe natural phenomena under natural conditions by looking carefully with their eyes.

Be careful when observing, don't let go of any subtle details. Zhuang Yueping, a student from Yunnan, spent 2_0_ days observing the whole process of pigeon hatching in detail. Almost every day, new discoveries are made, even a black spot on the pigeon and wrinkles on its eyelids are not let go. Therefore, this article "Observing Pigeon Hatching" is true and rich in content. At the same time, the observation should be recorded in detail, otherwise it is impossible to get real first-hand materials.

2. Hands-on experiments. The experimental method is to artificially intervene and control the research object, which is more conducive to giving full play to the initiative of students to reveal hidden natural mysteries than observation.

What do insects do with their hind legs? Zhang Jun, a student from Hubei Province, has successively caught more than a dozen insects such as locusts, grasshoppers and crickets, and cut off their hind legs. Through repeated experiments, observations and comparisons, many special functions of insects have been discovered.

3. Field trip. Including investigation, visit and field trip. Before the inspection, the purpose of the inspection and the necessary tools, instruments, medicines, daily necessities, etc. must be made clear. Must be prepared. In the process of inspection, it is necessary to record the time, place, process and inspection results in detail at any time and place, and sometimes bring back necessary specimens and samples to take pictures of more important phenomena. These are very useful first-hand information.

4. Get information. Due to the limitation of time, space or objective conditions, it is impossible to observe, experiment and investigate some materials in person, so we have to consult books and periodicals or consult teachers and parents. This indirectly obtained material is called second-hand material. Some problems can't be solved by your knowledge level, ability and conditions. This problem must be solved in your topic selection, so you have to check the information and find out.

(2) Analysis

After obtaining the materials, it is necessary to conduct analysis and research, select materials that can be used as arguments, select the essence according to the arguments, discard the false and retain the true, sort out and analyze according to the scientific attitude, and get your own arguments and opinions.

First of all, we should check the authenticity of various materials. Some of the materials we consult are outdated views, some explanations are only applicable to a certain range, some materials are not universal, some materials are recorded incorrectly or are fictional. This material should be used resolutely.

Secondly, we should pay attention to the typicality of materials, that is, choose materials that can explain the problem, not too much, but fine, and discard materials that have nothing to do with the argument or have little to do with it.

Thirdly, it is an argument to classify the selected materials, study their similarities and differences, and the relationship between them, and then draw a conclusion. The thesis argument comes from the analysis and research of materials, so we can't draw a conclusion first, and then find the materials suitable for proving the argument. For example, Xiong studied the eyesight of earthworms. She chose four materials (1) and shook them in front of earthworms with wooden sticks, red scarves and pencils. (2) the response of earthworms to various foods; (3) the response of earthworms placed at home; (4) Please ask Grandpa to get information about whether earthworms have eyes. Through the analysis of the first three experiments, it is preliminarily judged that earthworms have no eyes, rely on their sense of smell to find food and rely on photoreceptor cells to find dark places. The fourth material further confirmed her inference and made the argument fully demonstrated and convincing.

Five, the writing of scientific papers

After sorting out and analyzing the materials, you can start writing. Although there is no fixed format, writing should generally follow the steps of asking questions, making assumptions, researching and analyzing, and drawing conclusions. Generally speaking, scientific papers should include the following parts.

title

The title is the "eyes" of the article. A good title is accurate, concise and attractive, which can give readers a fresh feeling and a deep impression, and play the role of making the finishing point.

The so-called "exact" means that the title of the article must summarize the central content of the article, so that people can see it at a glance, and they can't digress or deduct the topic, let alone use exaggerated words. The so-called "conciseness" means that the index questions should be refined, comprehensive, and focused, so as to be concise.

begin

There are many ways to start, depending on the research content and your favorite writing style, but generally speaking, you should come straight to the point and ask the questions you are discussing. How did you come up with the idea of studying this problem?

The article "Why Guiyang is the Second Spring City of the Motherland" begins: "I live in Guiyang, and I often hear people say that' Kunming is the Spring City and Guiyang is the Second Spring City'. As for why, I don't understand. I am determined to record the weather forecast and see if Guiyang is really the second spring city. " The desire to verify its scientific nature stems from such a sentence.

The problems in some articles are produced and discovered by accidental observation. You can also describe the process in chronological order from the beginning, and then ask questions at the right time.

main body

That is, analyzing and solving problems. It includes hypothesis, observation, experiment, investigation process, phenomenon discovery, judgment, reasoning and conclusion, which is the core part of the paper.

It should be noted that the research steps should be carefully written, the experimental process, data and the origin of phenomena should be clearly written, and the narrative should be in a certain order. The data materials should be accurate and can be designed into tables and charts that can explain the problem. If necessary, photos and collected specimens can be attached to enhance persuasiveness. The conclusions drawn should have their own unique opinions, be consistent with the arguments and have strict logic. Words should be concise and vivid, with distinct levels and clear organization.

final result

At the end of the article, you should write down your conclusions and suggestions on a certain problem.

At the end of the article "Vision of Earthworms": "Oh, I see, earthworms are completely blind. They rely on their sense of smell to find their favorite food, and use photoreceptors to distinguish the intensity of light. "At the end of the conclusion, echo the questions raised at the beginning and get good results.

After the first draft of the paper is completed, it will be revised repeatedly. See whether the beginning is concise, whether the argument is typical and true, whether the argument is logical, whether the argument is novel and coherent, whether the paragraphs are naturally connected, and whether the language is smooth and accurate. Let the classmates and teachers help to revise, and gradually improve after the revision. Finally, send it to the newspaper for publication or participate in small paper competitions at all levels.

Doing experiments is my favorite form of entertainment. I often go to bookstores.

Read some books to do experiments, and then go home and do experiments by memory.

On this day, I came to the bookstore again and suddenly found a strange experiment: match dancing. Can you believe that naked matches can dance in the water? I can't believe it. I came home with a curious heart, ready to solve my doubts by doing experiments.

Back home, as usual, I started the experiment from memory.

I brought a basin of water, a match and a bottle of "all-purpose glue". I applied a thick layer of "all-purpose glue" to the match head, and then carefully put the match into the clear water. After waiting for a while, I didn't see any response. I calmed down and waited patiently. A few minutes passed. "Miracle" really appeared! I saw matches standing upright in the water and dancing with the swing. However, in less than half a minute, the match floated on the water again. A few minutes later, the match began to dance again. This cycle lasted seven or eight times, and the match never moved again.

What magical power drives matches to "dance"? My mind is full of doubts and I can't figure it out. Finally, my silent teacher, the computer, helped me. It turns out that when the "all-purpose glue" comes into contact with the phosphorus on the match head, it will produce a substance. The more this substance accumulates, the more it will make the match stand upright. When this substance volatilizes, matches are driven to dance. After a while, the outermost substance of the matchhead evaporated and the match did not move. During this time, the generated substances gather again, and the matches "dance" again until the reaction between the all-purpose glue and phosphorus is over.

At this moment, I suddenly realized: Ah! Matches can dance, so that's it.