My sister has three questions to answer. Please help kind people. The question is as follows.

I: Which is stronger in basic education between China and America-primary and secondary education/study abroad/international/secondaryedu/31855.shtml.

Comparison of educational development level between China and America.

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Ⅱ: When it comes to tourism, people often think of international tourism. In fact, domestic tourism is also an extremely important part of tourism. From the combination of theory and practice, it is of great significance to deeply understand the position, function and development conditions of domestic tourism.

First, the position and role of domestic tourism in the national economy

Domestic tourism is an important consumption form of social citizens, and its development is a symbol of the improvement of national living standards. China's domestic tourism has developed to a certain scale and influence today, but it is still in a state of spontaneous disorder. In order to change this situation and make domestic tourism develop as soon as possible, we must first improve our understanding of the position and role of domestic tourism in the national economy.

First, the development of domestic tourism has the functions of withdrawing funds, promoting market prosperity and ensuring the stable development of the national economy.

Since the Third Plenary Session of the Eleventh Central Committee, the living standard of China people has improved rapidly, and the purchasing power of residents has greatly increased. At the end of 1980, the scraping purchasing power was only 80.4 billion yuan, which increased to 250 billion yuan in 1985 and 703.4 billion yuan in 1990. In ten years, the average annual growth rate was 25%. Such a huge purchasing power not only reflects the increase of income of urban and rural residents and the improvement of people's living standards, but also is a hidden danger to stabilize the market and society. How to guide the purchasing power of the remaining residents is an important issue to ensure the stable development of the national economy. At present, securities investment and consumption of high-grade durable consumer goods have become important ways to guide residents' purchasing power to climb upward, but they can't completely solve the problem of currency withdrawal. In recent years, residents' securities investment has made great progress. However, because the development of the investment market is still in the primary stage, the scale of attracting residents' purchasing power to invest is still limited, and high-end durable consumer goods in the consumer goods market have played a great role in absorbing residents' purchasing power. But in recent years, it has been saturated. In the case that securities investment and high-grade durable consumer goods can not completely alleviate the upward pressure of residents' purchasing power, developing domestic tourism, absorbing a large amount of consumption funds and withdrawing funds has become another important way to guide residents' purchasing power to rise upward. According to the statistics of the World Tourism Organization, in 1990, the world's domestic tourism income reached 2.4 trillion US dollars, and the total international tourism income reached 2.65 trillion US dollars, which kept pace with important industries such as energy and automobile manufacturing and became one of the three major industries in the world economy. In recent years, China's domestic tourism industry has also developed rapidly, and its economic benefits have been continuously improved. During the Seventh Five-Year Plan period, the number of domestic tourists was 654.38+0.39 billion, with an average annual income of 75.3 billion yuan and an average annual income of 654.38+0.05 billion yuan. 192 The number of domestic tourists reached 330 million, and the funds for returning home reached 25 billion yuan. Practice has proved that properly guiding people's tourism consumption and developing domestic tourism are indeed effective ways to withdraw funds, reduce market pressure and promote national economic development.

Second, the development of domestic tourism can provide more employment opportunities. Tourism is a comprehensive service industry. To meet the various needs of tourists, it is necessary to develop corresponding industries that provide services directly and indirectly. According to estimates, for every person directly employed in the tourism industry, the number of people indirectly employed in society can increase by more than five. Therefore, developing tourism to promote the development of the tertiary industry can provide a large number of employment opportunities for people.

Third, the development of domestic tourism can also promote the development of other industries and improve the national economic structure.

The development of tourism should not only be based on the development of certain material production, but also promote the development of economic sectors and improve the national economy. This is because the development of tourism can stimulate the consumption of tourists, thus forming and expanding a new consumer market. In order to meet the expanding consumption due to the development of tourism, it is necessary to increase production and expand services. Tourism-driven consumption is a high-level consumption, and the requirements for consumer goods and services are relatively high, both in quality and quantity. In terms of upgrading, the cycle of some tourism consumer goods is shorter, which puts higher demands on the production and service departments. Therefore, this new form of tourism consumption has become a new driving force to promote the development of production, and may open up new production channels for other departments and industries. At the same time, the development of tourism will also promote the exchange of various economic information and provide conditions for the emergence of new industries. These functions of domestic tourism can promote the adjustment and improvement of the national economic structure.

Fourthly, developing domestic tourism can also revitalize and prosper the local economy.

China has a vast territory and abundant resources, and is rich in tourism resources. All localities can proceed from local reality, develop domestic tourism according to local conditions and promote local economic development. Especially in some areas with low economic level and rich tourism resources, developing domestic tourism is a better way to prosper the local economy. Nanzheng County in Hanzhong, Shaanxi Province was once a poverty-stricken county subsidized by the state for a long time. However, in recent years, the total output value of industry and agriculture has jumped to the first place in Hanzhong, becoming one of the counties with fiscal revenue exceeding 50 million yuan. One of the reasons for this great change is that in recent years, Nanzheng County has opened a new South Lake scenic spot and vigorously developed tourism. Rural farmhouses near Huangguoshu Waterfall in Guizhou used to be low and crude stone houses, and many villagers lived on government relief. In recent years, with the increase of tourists, various tourist service facilities have been built one after another. Farmers who used to be unemployed are now starting businesses, and some have made a fortune. 1988, the town's savings reached 4180,000 yuan, making it a famous town with ten thousand households. Tourism not only promotes the economy of backward areas, but also obviously promotes the economy of developed areas. For example, some big cities in Europe and America, the take-off of the four little dragons in Asia and so on. Tourism has played an important role. 199 1, Shanghai has put forward "three ones" requirements for travel agencies engaged in domestic tourism, that is, attracting every stranded guest to stay in Shanghai for one more night, upgrading the tourism grade by one grade and shopping for one hundred yuan more. Through work, domestic tourists stayed in Shanghai for 2 13 days in the first half of 992. Most of them have stayed in two-star hotels, and a few have stayed in three-star hotels. The average shopper in Shanghai has reached 900 yuan. If one tenth of Shanghai's migrant population can reach this level through work, it will be tens of billions of consumption, which will greatly promote Shanghai's commerce and textile industry.

Fifth, the development of domestic tourism can also accumulate funds for national construction and play a positive role in improving the economic benefits of the whole society.

Vigorously developing domestic tourism and encouraging people to increase tourism consumption will achieve more profits for the country and society, thus accumulating funds for national economic construction. At the same time, due to the special industrial function of tourism, the multiplier effect of developing tourism is more obvious in improving the economic benefits of the whole society. According to the scale of 300 million domestic tourists a year in China, the domestic tourism income can reach181800 million yuan, which is about equal to1740 billion yuan of China's gross national product. According to China's current consumption level, the direct income per 1 yuan can generate a total economic benefit of 3.03 yuan, so the direct economic income of181800 million yuan will generate a total economic benefit of 5508.5 yuan. It can be seen that it is indeed an important measure with positive effect to improve social and economic benefits by developing domestic tourism.

Sixth, the development of domestic tourism is conducive to national cultural exchanges, emancipating the mind, renewing ideas, promoting the construction of spiritual civilization and improving the quality of life.

First of all, developing domestic tourism is an important way to meet people's growing material and cultural needs. With the development of economy and the improvement of people's living standards, the desire to travel is getting stronger and stronger, and the number of people traveling abroad is increasing day by day. Developing domestic tourism has become the only way to meet people's growing material and cultural needs. Secondly, the development of domestic tourism plays an important role in stimulating people's patriotic enthusiasm, improving people's health level and improving the quality of life. Tourists visiting the magnificent mountains and rivers and places of interest in the motherland have a positive effect on broadening their horizons, cultivating their sentiments, expanding information exchange and enhancing their physical and mental health. Especially in the patriotic education of teenagers, the role of domestic tourism is more obvious. In the past, activities such as "summer camp" study week were carried out, including ideological education and imparting knowledge about tourism, so that young people could learn what books could not learn and stimulate their enthusiasm for rejuvenating China. These forms can provide reference for the development of domestic tourism. Thirdly, the development of domestic tourism can also promote the renewal of ideas, thus improving people's quality. The tourist flow formed by the development of domestic tourism is the carrier of information flow and concept flow. The dissemination of these information, ideas, thinking and lifestyles can play a role in breaking the local closed and conservative concepts and triggering the renewal of thinking concepts. An important reason for China's social and economic backwardness is that closed and ignorant thoughts hinder social progress. By developing domestic tourism, strengthening ideological and cultural exchanges between people and renewing ideas, its significance is far more profound than the economic benefits obtained by developing tourism. As for the role of domestic tourism in the construction of spiritual civilization, it has been more and more recognized by people. Arthur Holod, former president of the World Tourism Organization, said: "We must make every effort to maintain tourism at the highest cultural and spiritual level. We must organize tourism to make it not only a good industry, but also a good opportunity to create a more civilized and peaceful world. " This is indeed an insight applicable to international tourism and domestic tourism. To sum up, domestic tourism is an industry with special functions. It plays a very important role in promoting the construction of socialist material civilization and spiritual civilization. Therefore, the development of domestic tourism should attract full attention from all walks of life, especially tourism.

Second, the relationship between domestic tourism and international tourism

To develop domestic tourism, we should not only improve our understanding of its position and role in the national economy, but also correctly understand and handle the relationship between domestic tourism and international tourism.

Human tourism behavior consists of domestic tourism and international tourism. The relationship between them can be expressed in two sentences: domestic tourism is the foundation and forerunner of international tourism; International tourism is the extension and development of domestic tourism. The development of tourism is inseparable from domestic tourism. Here, as long as we focus on analyzing the relationship between domestic tourism and the whole tourism industry, its relationship with international tourism will be clearer.

First of all, domestic tourism is the forerunner of tourism. Generally speaking, a country's tourism industry first developed from domestic tourism. People's travel behavior, from the direction and scope of travel, first starts from short-distance travel, that is, domestic travel. When the domestic or local economy develops to a certain level, it begins to turn to international tourism and long-distance tourism. Based on the needs of social and economic development, China has chosen the road of giving priority to the development of international tourism to stimulate the economy to absorb foreign exchange. However, the leading role of domestic tourism is still undeniable. Secondly, domestic tourism is the basis and subject of the whole tourism industry. According to the statistics of the World Tourism Organization in recent years, domestic tourists account for more than 90% of the world's tourists, and their income accounts for nearly 90% of the world's tourism income. The annual ratio of overseas tourists to domestic tourists in the United States is1:100; In the mid-1980s, the number of domestic tourists in Britain also accounted for 86% of the total number of domestic tourists in that year. According to the statistics of China National Tourism Administration, the number of people entering China in110,000 in 1990 was 2 1 10,000, and the foreign exchange earned was 109 billion yuan. However, according to incomplete statistics, during the same period, the number of domestic tourists reached 280 million, and the currency returned was/kloc-0.7 billion yuan. 1992, the number of inbound tourists in China rose to 38165438+50,000, and the foreign exchange income was 3.94 billion dollars. In the same period, the number of domestic tourists reached 330 million, and the currency returned was 25.2 billion yuan. Therefore, no matter the relationship between supply and demand of tourism, the hardware and software of tourism service facilities, or the comparison between tourists and income, it has fully proved that domestic tourism is the foundation and leader of the whole tourism industry. Thirdly, domestic tourism is an important means to adjust the tourism market and improve the utilization rate of tourism facilities. The international tourism market often fluctuates due to political, economic or seasonal reasons. Domestic tourism can make up when the international tourism market fluctuates, adjust the utilization rate of tourism facilities, and solve the problem of idle and saturated traffic. Paying attention to the adjustment means of domestic tourism can prevent the imbalance between the development of international and domestic markets and avoid the situation that the tourism economy depends entirely on the international market without room for manoeuvre. Then, the development of domestic tourism can also appropriately control the number of people going abroad and narrow the deficit of tourism revenue and expenditure. In the past, the tourism deficit in the United States was quite prominent. In recent years, the government has vigorously carried out activities to love new york and used the 200th anniversary of the founding of the People's Republic of China to attract domestic tourists. For the same purpose, Switzerland put forward the slogan "It is more convenient and appropriate to spend a holiday at home".

According to the above analysis, domestic tourism should not be neglected in the development of tourism, and the relationship between the two should be handled well to promote the healthy and sustainable development of the whole tourism industry.

Three. Conditions for developing domestic tourism

In the middle and late 1980s, China's tourism industry thought that domestic tourism had not yet formed the scale and conditions, and it was not suitable for vigorous promotion and development. Nearly ten years have passed, and the conditions for developing domestic tourism in China have changed greatly. First of all, economic development and the improvement of national income have laid an economic foundation for the development of domestic tourism.

According to the world-recognized empirical data, when the per capita GNP reaches $300, residents have the motivation to travel in China; When it reaches $ 1000, I want to travel to nearby countries; When it reaches 3000 dollars, I want to travel abroad. At present, the per capita GNP of China is about 340 dollars. Although it only crosses the boundary of domestic tourism motivation, in the coastal areas with developed commodity economy such as Fujian, Guangdong, Jiangsu and Zhejiang, the improvement of people's living standards is more significant due to the huge difference in economic development level. The demand for domestic tourism in these areas is bound to be stronger than that in other areas. At the same time, judging from the national savings balance, by the end of 199 1, the savings balance of urban and rural residents has reached more than 9 1000 billion yuan, which has already possessed the basic economic conditions for generating domestic tourism motives. These conditions prove that the conditions for developing domestic tourism are basically available objectively. Second, the rich in China.

Tourism resources are an important condition for developing domestic tourism. Third, China has implemented paid holidays and a 44-hour working week, which has provided conditions for the development of domestic tourism. One of the important tea items that produce tourism behavior is that people should have enough leisure time. In economically developed countries, citizens have more leisure time to provide conditions for travel because of paid vacation, 40-hour working week and more legal holidays. Moreover, after more than ten years' development, China's tourism industry has begun to take shape, and it has enough facilities to develop tourism. According to the statistics of National Tourism Administration, there are 2,354 foreign-related hotels in China, with 3,565,438+10,000 rooms and 737,700 beds, which is three or three times that of 1985. In addition, in terms of transportation, as of the end of 1989, the national passenger traffic was 7913.73 million, including railway138.05 million, highway 6,445.08 million and waterway 317.78 million,/kl. In terms of communication, there are 5,306 carrier telegrams, 33,379 teleprinters and 2,600 fax machines in the national 17-03748 1 telephone exchanges and 1083275 telephones. These hardware, except traffic is still a "bottleneck", have been greatly improved in other aspects. Many tourist reception points have seen the phenomenon of excess tourist facilities and insufficient food in the off-season. The reception capacity of these devices will be combined with more domestic tourist facilities to form a greater reception capacity. Finally, the number of domestic tourists organized by travel agencies has increased sharply, indicating that the domestic organized tourism market has formed a certain scale. According to the statistics of 2456 second-and third-tier travel agencies in China, 1992 * * * group received 282 1000 domestic tourists, accounting for 6. 66 times that of last year. Compared with overseas tourists organized by China in those years, domestic tourism greatly exceeded. This indicates that China's domestic tourism industry has changed from spontaneous tourism in the past to organizing tourism through travel agencies. At the same time, it also marks the basic formation of China's domestic tourism market, and the conditions for developing China's domestic tourism are basically available.

Fourth, take effective measures to vigorously develop domestic tourism.

According to the requirements of China's economic development strategy, the gross national product will quadruple by the end of this century. According to the situation in recent years, it is likely to be realized three years ahead of schedule. With the development of economy and the improvement of people's living standards, people's demand for tourism is getting stronger and stronger. In this regard, we should actively guide and make preparations as early as possible to ensure the healthy development of domestic tourism.

First, deepen the understanding of the position and role of domestic tourism in the national economy. For a long time in the past, China implemented the policy of "no promotion, no publicity and no opposition" to domestic tourism, and domestic tourism was gradually put on the agenda, but the relevant departments still did not pay enough attention to the demand for domestic tourism and lacked necessary planning and practical guidance. In the future, we should publicize the position, function and development conditions of domestic tourism through theoretical seminars, newspaper propaganda and so on, so that the development plan of domestic tourism economy can be realized in a planned and step-by-step manner. In the adjustment of industrial structure, we should take domestic tourism as the key support object; In terms of specific policies, preferential treatment will be given to the construction and restoration of key tourism infrastructure, key tourist attractions and the production of important tourism commodities, creating conditions for the vigorous development of domestic tourism.

Second, establish the policy of developing domestic tourism moderately and strengthening domestic tourism infrastructure construction simultaneously, and actively realize the balanced development of domestic tourism. Domestic tourism needs great development, but it is also restricted by traffic capacity. Take the railway as an example, there are more than 20,000 kilometers of lines operating "with diseases" in China. More than 200 buses made in 1930s are still in overdue service. Most railways leading to tourist hot cities are overloaded by 50%. The traffic bottleneck is still very serious. Faced with this situation, on the one hand, the development of domestic tourism should adapt to traffic conditions. Short-term tourism should be advocated in the near future, and long-term tourism should be organized appropriately. On the other hand, it is necessary to increase infrastructure construction and actively balance short-term industries.

Third, strengthen macro-management and actively coordinate and solve the contradictions between domestic and foreign tourism. Domestic tourism and international tourism are both unified and contradictory. Since the reform and opening up, a large number of overseas tourists have flooded into China. With the development of economy and the improvement of national life, domestic tourism is also on the rise. In some tourist hotspots, the ratio of domestic tourists to overseas tourists is as high as 70: 1, which has caused some contradictions. This contradiction should be solved in a positive way. On the one hand, we should strengthen industry management and tourism market management, and actively realize the combination, coordination and diversion of domestic tourism and international tourism. On the other hand, further develop local tourist attractions and new tourist attractions and routes, advocate short-distance tourism and new tourist routes, and reduce the pressure of tourist hotspots.

Fourth, improve the tourism service system and strengthen domestic tourism management. We should vigorously strengthen the construction of domestic tourism facilities, and set up professional travel agencies where conditions permit. Improve the degree of organization of domestic tourism and gradually realize standardization and serialization. Further improve the domestic tourism service system. According to the consumption habits and level of domestic tourists, we will build accommodation, catering, transportation, sightseeing and entertainment facilities suitable for their needs.

Fifth, strengthen the education and training of tourism professionals and provide a large number of qualified talents for the development of domestic tourism. We can focus on international tourism training, and the management mode of international tourism can be applied to domestic tourism, but domestic tourism has its own characteristics and laws after all. Therefore, there should be new changes in the training content and aspects of employees in order to train and provide a large number of talents to meet the needs of domestic tourism development. In a word, although the development of domestic tourism still faces many difficulties and problems, as a new industry, its development prospect is very considerable. As long as we raise our awareness and take practical measures. With the positive development, domestic tourism is bound to have a new and dynamic situation.

Ⅲ: Silicon is a semiconductor material that can stand the test of device technology development better than germanium. 1966 has produced 40,000 kilograms of semiconductor-grade silicon (single crystal ultra-pure silicon with impurity content less than1109), thus manufacturing 4 billion components. By 1966, the amount of silicon used in this field has exceeded the amount of germanium.

The integrated circuit composed of silicon transistors and other components is getting higher and higher in integration and scale, while the components are getting smaller and smaller. A silicon wafer with a diameter of 75 mm can integrate tens of thousands to hundreds of thousands or even millions of components to form microelectronics, thus appearing microcomputers and microprocessors.

Growing a layer of 10-25 micron thick polysilicon film on aluminum substrate is a cheap and lightweight solar cell material, which is suitable for use in space and on the ground.

Silicon is the main material of isotope battery transducer. Transducer is a device that converts the thermal energy of isotope heat source into electrical energy. The working temperature of the transducer made of silicon germanium alloy is 1000oC, which has good mechanical properties and oxidation resistance, is not easy to evaporate and be poisoned at high temperature, and can work in vacuum and air.

The heat-resistant lightweight silicon tile used in the space shuttle can protect the fuselage from the high temperature exceeding 1000oC when the space shuttle returns to the atmosphere.

The use temperature of natural rubber and synthetic rubber is generally below 150oC, otherwise it will age and deteriorate. Silicone rubber, developed in the 1940s, is a semi-inorganic polymer elastomer with silicon-oxygen-silicon as the main chain. It has some characteristics of inorganic materials and organic materials, and has a wide range of application temperatures. Silicone rubber has excellent ozone resistance, alkali resistance, physiological inertia (it has no adverse effects on human body and can be used as a repair material for some organs, such as artificial joints) and electrical properties. Some silicone rubbers with special structures have excellent oil resistance, solvent resistance and radiation resistance, so silicone rubbers are widely used in aviation, aerospace technology, electrical and electronic industries.

Using 1 10-2 methyl vinyl silicone rubber as raw rubber and acetylene black as filler, conductive rubber can be made, which is an ideal conductive material for connecting integrated circuits and LCD screens in electronic watches.

Silicic acid can form gel in water, so it can be used to prepare adsorbent-silica gel. Silica gel is a polar adsorbent, which has strong adsorption capacity for polar substances such as H2O, and is often used as desiccant and adsorbent in industry.

The aqueous solution of sodium silicate is called sodium silicate, and it is called sodium silicate in industry. Wood and fabrics soaked in sodium silicate can be antiseptic and not easy to catch fire.

Silica sol is an aqueous dispersion with silica as the basic unit. In the process of wool textile, it can be used as a sizing agent for light textile to reduce the broken end rate of wool fibers. The coating contains silica sol, which can improve the surface heat resistance of inorganic fiber materials.

In the enamel ware manufacturing industry, the addition of silica sol can reduce the expansion coefficient and improve the adhesion to tetrafluoroethylene, which has the same effect in glass and glass ceramics. If 25-30% silica sol is added to the glass, high quality borosilicate glass can be made.

Some sodium borosilicate glasses (including sodium oxide, boron oxide and silicon oxide) are separated into two immiscible parts after heat treatment and atomic recombination. One part mainly contains silicon oxide, and the other part mainly contains sodium oxide and boron oxide. If treated with acid again, silicon dioxide will not be affected by acid, while sodium oxide and boron oxide will be dissolved in acid, leaving many holes-micropores, thus making widely used microporous glass.

Drying and sintering the microporous glass to obtain transparent glass with high silica content. It has the advantages of high temperature resistance, good thermal stability and strong ultraviolet transmittance. It can replace timely glass in many aspects and is suitable for high temperature observation windows, such as those on spacecraft. Forcing it to observe objects will not deform, because its optical uniformity is also very good.

If a small amount of silver halide is added to the ordinary sodium aluminum borosilicate glass as sensitizer and a small amount of copper is added as sensitizer, the photochromic glass of silver halide can be made by melting, annealing and proper treatment with conventional glass technology. It will change color due to different light intensity, and has important applications in strong light protection, display devices, optical information storage, vehicle windshield and so on.

Pure silicon crystal is called chronotropic. It melts into viscous liquid at 1600℃ in time, and the inside becomes irregular. When it is cooled again, it is difficult to recrystallize because of its high viscosity, and it becomes timely glass. It has many special properties, such as allowing visible light and ultraviolet light to pass through, and can be used to make ultraviolet lamps and optical instruments; It has a small expansion coefficient, can withstand drastic changes in temperature and has good acid resistance (except hydrofluoric acid), so it is often used to manufacture advanced chemical utensils.

The optical energy transmission system equipped with medical laser is made of Shi Ying optical fiber, which is not only exquisite, light and flexible, but also can transmit laser energy into human internal organs for treatment.

Double quick cement is a new type of cement, which has the characteristics of quick setting and quick hardening. The strength after pouring for one day is equivalent to that of ordinary cement pouring for 7-28 days. It can be used for slipform construction, rapid molding and demoulding of prestressed concrete members and blocks, and can also be used as self-hardening sand for the molding of shotcrete or mechanical castings in mine roadway.

Spongy elastomer made of waste tires, etc. Mixing and stirring with super glue emulsion and cement to form rubber cement. It overcomes the shortcomings of the original concrete, can prevent cracking, peeling and water absorption, and can be used for paving and building.

SiC is also called silicon carbide and emery. It has diamond-like structure, high hardness and high decomposition temperature, so it is widely used as abrasive in industry.

Silicon nitride ceramics have high strength and hardness, good thermal shock resistance and chemical corrosion resistance, low friction coefficient and self-lubrication, and are excellent wear-resistant materials. After hundreds to thousands of hours of operation, the mechanical sealing ring made of silicon nitride ceramics has less wear and the service life is several times to ten times longer than that of raw materials.

After being heated to a certain temperature, the silicon carbide far-infrared radiant panel based on silicon carbide ceramics can emit long-wave infrared rays above radiation 2- 15 micron, and has high drying efficiency for organic matter, polymer substance and water-containing substance with strong absorption peak of far infrared rays. At present, this silicon carbide far-infrared radiation board has been applied to bicycles, sewing machines and furniture. Drying of wood, leather, textiles, food and grains.